30 December 2005

Tropical Storm Zeta forms...

Go ahead, re-read the subject; it did NOT say "Winter Storm Update 
12/30".  Continuing an unprecedented tropical season (and post-season), 
the 27th named storm, Zeta, has formed today in the eastern Atlantic, 
south of the Azores.  Satellite-estimated intensity is 45kts and 1003mb.
It's located at 25.0N 36.9W and tracking NW at 7kts.  It has healthy 
deep convection centralized over the core, and several banding features.  
It's in about 20kts of westerly shear and is over 23C water.

The forecast is bleak for the storm, possibly strengthening briefly in 
the next 24 hours, then rapidly dissipating in increasingly hostile 
conditions as it turns toward the west.

The formation of Zeta brings the season's NTC up to 268% (an average 
season is defined to be 100%)


Please visit my tropical Atlantic headquarters.

07 December 2005

Yet another record for the 2005 hurricane season

From Phil Klotzbach:

According to the monthly data that I have since 1950, December 2005 has now posted the highest NTC of any December on record with 8.8%.  It broke the old record of 7.7% set in 1984.  December 2005 also has the record for most named storm days (7) and hurricane days (5.25) ever in a December.  

Please visit my tropical Atlantic headquarters.

06 December 2005

Epsilon... and what lies ahead?

At 15Z, Epsilon was still a hurricane, much to the dismay of enervated 
forecasters at NHC.  It's located at 31.9N 33.8W and now moving S at 
8kts.  Satellite-estimated intensity is 65kts and 987mb.  Although it 
still has deep convection wrapped around the center, the circulation is 
beginning to elongate.  It's forecast to weaken in the face of increasing 
shear and head southwest toward the tropics over the next 5 days.  While 
the track has been fairly easy to forecast, the intensity has not, so at 
this point, take the intensity forecast with a grain of salt... Epsilon 
has not cooperated with our typical understanding of tropical systems!

Bill Gray and Phil Klotzbach (also here at CSU) have released their 
forecast for the 2006 hurricane season (this is the 23rd seasonal 
forecast made at CSU, by far the most experienced team!).  As expected, 
it calls for another very active season, with 17 Named Storms, 9 
Hurricanes, and 5 Intense Hurricanes, or about twice the average.  With 
this heightened activity, US landfall probabilities are also higher than 
average again.  To the first order, activity in the Atlantic undergoes a 
40-60 year oscillation, and for the past 10 years we have been in the 
active phase of this oscillation, and probably will be for another 10-15 
years before it slows down.  A period very similar to this was seen in 
the 1940s through mid 1960s, then from the mid 60s through mid 90s, the 
basin was relatively dormant.
For full details of the forecast and the six long lead-time predictors 
used, visit http://hurricane.atmos.colostate.edu/Forecasts/2005/dec2005/

To bring you up-to-date on the NTC, it's now 264.5%.


Please visit my tropical Atlantic headquarters.

05 December 2005

Tenacious Epsilon still a hurricane...

Epsilon has now been a named storm for as long as the mighty Katrina, 
and could still have a few days left, at least!  Despite cold SSTs (21C) 
and strong vertical shear (35kts), the hurricane maintains a beautiful 
large eye and persistent deep convection in the eyewall... baffling 
forecasters.  This is truly the season that does not want to end.

The latest position is 33.6N 35.1W, or about 7 degress southwest of the 
Azores.  Satellite-based intensity estimates are 70kts and 982mb.  Going 
with persistence, one would expect it to maintain this intensity.  Going 
with physical reasoning, one would expect it to weaken rapidly.  When in 
doubt, go with persistence!  It's currently moving ESE at 7kts.

The future is very questionable, as evident by the poor intensity 
forecasts.  Models and forecasts alike have been predicting weakening, 
but it refuses to lose hurricane status.  Forecasts made as recently as 
Sunday said that by this time, it would be a 35-40kt remnant low or 
extratropical cyclone... instead, it's a healthy CAT1 hurricane!  The 
official intensity forecast still calls for weakening, but they admit 
that forecast has almost no certainty.  The forecast track is very 
interesting: it's expected to cease eastward movement and turn back to 
the southwest toward the tropics.  This storm could be around for many 
more days, extending the already-extended record-smashing hurricane 
season.

As of 15Z today, the NTC stands at 263.4%, and is rising at a rate of 
1.1% per day while Epsilon is a hurricane.


Please visit my tropical Atlantic headquarters.

02 December 2005

Epsilon upgraded to a hurricane...

Although the official hurricane season ended two days ago, at 15Z today, 
Epsilon was upgraded to a hurricane, making it the 14th of the year (the 
"average" number is 6).  The previous record for number of hurricanes in 
a season was 12.  Epsilon became somewhat less organized yesterday, but 
today looks much better... more symmetric, more convection, more 
outflow.  It once again has an eye.  It's in about 20kts of westerly 
shear and the SST is about 24C.

Satellite-estimated intensity is 65kts and 987mb, and it's moving NE at 
12kts.  Current location is way out at 33.7N 48.2W, safely in the north 
central part of the basin between the Azores and Bermuda.  It is forecast 
to gradually weaken and continue a northeast motion.  Over much colder 
water, it should decay to a fossil cyclone in a couple days.

This now brings the seasonal Net Tropical Cyclone activity up to 261%, 
meaning that 2005 has been about 2.6 times more active than an average 
season.


Please visit my tropical Atlantic headquarters.

30 November 2005

Epsilon strengthens...

Today is the last day of the official hurricane season, but apparently 
nobody told Epsilon, which is still out there and going strong.

The satellite presentation today is beautiful; there's symmetric 
outflow, nice banding features, and an eye/eyewall forming.  This visual 
appearance plus some help from other remote sensing techniques gives an 
estimated intensity of 55kts and 993mb.  It could strengthen further 
before transitioning to an extratropical cyclone this weekend... 
possibly reaching hurricane status.  It's tracking W at 8kts, but should 
begin a northeasterly movement tonight.  As of 15Z, it's located at 
30.7N 53.9W, or about 10 degrees ESE of Bermuda.

As a quick season wrap-up, we've seen 26 storms reach Tropical Storm 
intensity or higher.  13 of those reached Hurricane status, and 7 of 
those reached Major Hurricane status (CAT3+).  The "average" numbers are 
10 Tropical Storms, 6 Hurricanes, and 2 Major Hurricanes.  Taking into 
account the numbers of storms and longevity of them compared to average, 
this season was over 2.5 times more active than an average season 
(257%).  In the Atlantic, we witnessed the highest number of named 
storms in recorded history (26), the lowest pressure in recorded history 
(882mb), and the costliest disasters in US history ($100 billion+).  
There are scores of other records too.  I'll eventually be sending out 
my full summary, but this is a good teaser!  Stay tuned!


Please visit my tropical Atlantic headquarters.

29 November 2005

Epsilon forms in central Atlantic...

As the 2005 tropical Atlantic season persists, Epsilon, the 26th named 
storm, formed this morning.  It's located about 14 degrees east of 
Bermuda in the north central part of the basin and its latest satellite-
estimated intensity is 45kts and 993mb.  It is heading W at 7kts.  SST 
under the system is about 25C and vertical wind shear is about 15kts 
from the southwest.

The forecast is for gradual strengthening (largely owing to decreasing 
shear), perhaps reaching hurricane status within the next couple of 
days, then transitioning to an extratropical cyclone.  It is expected to 
drift westward for the next 1-2 days, the zip off to the ENE as it gets 
caught up in the mid-latitude westerlies.

As an aside, Delta became an extratropical cyclone and hit the northwest 
coast of Africa and the Canary Islands as a very potent storm.  It was a 
named tropical storm for 5 days.

The NTC for 2005 is now 257%.  The season has not been one to break 
records, it has been one to shatter them.  As most of you know, I send 
out a season summary each year at the end of the season.  I still plan 
on doing this, but it probably won't come out on Dec 1.  Eventually...


Please visit my tropical Atlantic headquarters.

An Old Record Tied

From Gary Padgett:
 
The formation of TS Epsilon in the Atlantic ties the
record for the most TS/HU forming post-30 September.
 
In 1887 there were 9 post-Sept TCs---six forming in
October (as in this year), and after a quiet month,
a little "mini season" in late Nov/early Dec, whereby
1 HU formed at the end of Nov, and another HU and
as TS formed during the first week of Dec, all in the
general region just north and northeast of the Greater
Antilles.   The two hurricanes eventually recurved
into the Atlantic, but the final one, a TS, formed
east of the Leewards and pursued an very unusual
WSW track across the entire Caribbean, eventually
moving into Costa Rica--the only TS on record to
make landfall in that country.
 
The second highest number of post-30 Sept TCs
was just 4 years ago, in 2001, with 7 named storms
forming in Oct and Nov.   If we can get a Zeta
during Dec, we can set yet another record for
the 2005 season.
 
Please visit my tropical Atlantic headquarters.

23 November 2005

TS Delta forms in the central Atlantic...

A strong subtropical storm has transitioned to tropical, and has 50kt 
sustained winds and a 982mb MSLP, making it TS Delta, the 25th named 
storm of this unprecedented season.  It is well away from land, located 
at 25.9N 40.5W and tracking SSE at 8kts.  The convection and outflow are 
very healthy, and while the SSTs are only 25C or so, the tropopause 
temperature is colder than average too, so the temperature DIFFERENCE 
between the inflow and outflow levels is still enough to support a 
hurricane.

The forecast calls for some strengthening, perhaps reaching hurricane 
status Thursday night into Friday morning, then becoming extratropical.  
The track is northerly at first (hence being nudged equatorward toward 
warmer SSTs) then southerly back into the mid-latitudes.

The NTC is now 253%.  If it is upgraded to a hurricane tomorrow morning 
(just supposing), the NTC would jump to about 256%.


Please visit my tropical Atlantic headquarters.

18 November 2005

TD27 becomes Gamma in this unprecedented season...

On Nov 13, an area of disturbed weather in the far eastern Caribbean Sea 
was upgraded to TD27, but remained poorly organized.  On Nov 16, the 
final advisory was written on it as it degenerated to an open wave.  
However, over the past couple of days, it has been left to fester in the 
western Caribbean Sea and has continually gotten better organized.  An 
aircraft recon flight into this afternoon found not only a closed 
circulation, but tropical storm force winds, making it the 24th named 
storm of the season, Gamma.

At 22Z, TS Gamma was located 16.4N 85.6W and creeping WNW at 4kts.  
Intensity measured by the aircraft is 40kts and 1006mb.  Its future is 
not too bright, as vertical wind shear impinges on it and it drifts 
closer to land.  However, the forecast track brings it northwest toward 
Cozumel/Cancun, then recurves and heads northeast toward the southern FL 
peninsula.

With this addition, the season's NTC stands at 251% (recall that an 
"average" entire season is defined as 100%).


Please visit my tropical Atlantic headquarters.

03 November 2005

perspectives on the 2005 ATL season

From Gary Padgett: 
 
One perspective on this season which I've found very interesting
is that the superabundant activity has been largely due to the
incredible amount of activity in July and October.   I've calculated
the Net Tropical Cyclone activity index (NTC) per Dr. Gray's
formula for each month from 1950-2004, and for the months
of this hurricane season.

(The NTC is an average of the six "cardinal" parameters---number of
named storms (NS), hurricanes (H), intense hurricanes (IH), and the
total number of days accumulated for each intensity level (NSD, HD,
IHD)---with each expressed as the percentage of the long-term average
over some baseline period.   The NTC for each month is calculated
by dividing that month's total NS, H, etc by the annual averages of
each parameter, then averaging the six percentages.)

The following table gives the average monthly NTC for the months
June - October for the period 1950-2004, followed by the 2005
NTC for that month:

Month     Avg. NTC    2005 NTC
==============================
Jun             2%          4%
Jul             4%         64%
Aug            25%         39%
Sep            48%         70%
Oct            16%         63%

The core months of Aug/Sep produced a total of 10 NS
with 7 H for a combined NTC of 109%.    While having
two hurricanes of the intensity of Katrina and Rita was
very unusual, otherwise the activity of the two main months
wasn't particular all that remarkable.   Many years have
had Aug+Sep totals of 10 NS and 7 H---last year had
12 NS and 8 H with an NTC of 208%.

October's is the highest NTC since 1950 (61%) and is
only the 3rd October on record to produce 6 NS, the
others being 1950 and 1887.

July's NTC of 64% wildly exceeds the previous high
July NTCs of 26% (1996) and 24% (1966), and the
5 NS forming during the month is a new record.


Please visit my tropical Atlantic headquarters.

31 October 2005

Beta hits Nicaragua hard...

Over the weekend, Beta wreaked havoc in Nicaragua and the offshore 
islands of Providencia and San Andres.  At 06Z on Saturday, Beta was 
upgraded to the 13th hurricane of the season, then at 06Z on Sunday, 
became the 7th major hurricane of the season just 50 miles off the 
Nicaragua coast.  The combined effects of very slow motion and 
intensification to a major hurricane caused tremendous rain to fall, and 
of course, flash floods.  Miraculously, no deaths have been reported 
yet, and only a few dozen injuries (this is preliminary).  Two big 
reasons are that the eyewall was very tiny, and more importantly, the 
citizens were warned and evacuated the coasts before the storm hit.

This is a welcome change of pace, after Katrina killed nearly 1100 
people, Stan killed over 1600, Wilma killed 38, and the list goes on 
with Dennis, Emily, Rita, etc.  Overall, a very costly and deadly few 
months.  From Arlene through Beta, the season's NTC is now a staggering 
249%, obliterating the past records for entire seasons.  There is 
exactly one month remaining in this hurricane season, and any further 
activity will just clinch the record even more firmly.


Please visit my tropical Atlantic headquarters.

28 October 2005

Beta STILL a tropical storm...

Although nearly every factor one looks at for rapid intensification was 
satisfied yesterday, apparently, something was awry, as TS Beta has 
strengthened only slightly.  The latest aircraft recon flight into the 
storm provided an intensity measurement of 55kts and 990mb, suggesting 
that it is nearly a hurricane.  The hindering ingredient could have been 
a nudge of mid-level easterly wind shear, sub-par oceanic heat content, 
or a combination of the two.  Normally the heat content is not critical 
for such a weak storm, but it is moving so slowly that it becomes more 
important.

Another element of the forecast that has not been very accurate is the 
track.  For at least a day now, computer and human forecasters have been 
expecting Beta to turn to the northwest then west in response to a 
developing ridge to the northeast.  This hasn't happened, and the storm 
is still moving north, at 4kts.  This could be a critical error because 
if it crawls just a bit more north THEN heads west, it has hundreds of 
additional miles of ocean (Gulf of Honduras) to track over and become 
strong, headed for Belize or Yucatan.  If it does indeed turn west very 
soon, it will dissipate over the mountainous areas of inland Nicaragua.  Either way, it is forecast to become at least a CAT1-2 hurricane.

Relating to yesterday's discussion of record NTC this season, I created 
a simple pie chart showing each of the 23 storms' contribution to the 
total value (Beta is current as of 21Z today).  I put the actual values 
next to the major contributors (Dennis, Emily, Katrina, Maria, Rita, and 
Wilma).  The names start at the top purple slice with Arlene, and work 
around counter-clockwise.     
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/2005NTC_pie.png

Please visit my tropical Atlantic headquarters.

27 October 2005

Beta forms in southwestern Caribbean...

The area of disturbed weather I've been mentioning all week was upgraded 
to TD26 at 03Z today, then further upgraded to TS Beta at 09Z today, 
making it the 23rd named storm of the season.

The satellite presentation is classic, and I see no reason why it would 
not continue to intensify at a respectable rate.  Microwave imagery at 
14Z revealed a compact and intense core under the CDO, and there are two 
major bands on either side of the center.  Shear is minimal, and SSTs 
are plenty warm, but the oceanic heat content drops off dramatically 
just to Beta's north, indicative of a shallow warm layer.

SHEAR:
http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8shr.html
SST:
http://www.nhc.noaa.gov/tafb/atl_anal.gif
HEAT CONTENT:
http://www.aoml.noaa.gov/phod/dataphod1/work/HHP/NEW/2005299ca.jpg

The official forecast takes Beta up to a CAT2 hurricane before drifting 
into the northern Nicaragua coast in several days.  The rainfall from a 
slow-moving tropical cyclone near mountainous terrain can be devastating.  
There is a distinct possibility that it will drift far enough north to 
miss Central America and head up toward the Yucatan or Cuba.

There are two other tropical waves out there that I've been discussing... 
one that exited Africa on Oct 19 and one that exited on Oct 23.  They 
are currently located at roughly 62W and 40W, respectively.  Both have 
been persistent, easily-tracked waves, but both have been suppressed by 
strong vertical wind shear.  However, conditions are gradually improving 
for the western one, which is just now crossing the Lesser Antilles.  
This has the potential to become TD27 or Gamma in the coming week.  
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/hovmoller/atlantic/

The NTC (Net Tropical Cyclone activity) is up to 236% as of 15Z today.  
This index takes into account the numbers of named storms, hurricanes, 
and intense hurricanes, as well as their respective longevities, and 
compares them to a climatological values of each.  An NTC of 100% would 
mean the June 1 - November 30 hurricane season was "average".

Today is the 300th day of the year, and "normally" we'd be talking about 
the 10th named storm, not the 23rd!  One of the principal drivers of 
activity in the Atlantic is the "Atlantic Multidecadal Oscillation".  
This is related to the basin-wide ocean circulation whose speed 
partially controls the SSTs and heat content.  Since 1995, this index 
has been positive, then was negative between 1970-1994, but before that, 
was mostly positive from the mid 1920s to late 1960s.  So, if history is 
a teacher, we should be in for a long period of this enhanced activity 
before the AMO swings back to the negative phase -- perhaps another 
20-30 years?  The problem is, there is a lot more life and property in 
harm's way during this active era compared to the last one 50-80 years 
ago!


Please visit my tropical Atlantic headquarters.

26 October 2005

Three active tropical waves keep the season alive...

It's easy to track coherent waves across the tropical Atlantic using 
this page:
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/hovmoller/atlantic/, 
and from it, you can see the one near 80W, 55W, and 30W.  They become 
less organized as you look east.  With that in mind, the westernmost 
wave is looking very interesting and is very close to becoming TD26 or 
even TS Beta.

The satellite presentation has improved markedly just during the day, 
with a banding feature to the north, and some deep convection forming 
near and wrapping around what appears to be a low-level center.  It is 
just east of Costa Rica and nearly stationary, perhaps a northwest 
crawl.  The forecast would be to develop it and continue a NW drift into 
Nicaragua.  The rain from this storm could be devastating to several 
Central American countries.

I'll just briefly point out that the next wave, at 55W, is heading into 
a more favorable environment so should also be watched closely.


Please visit my tropical Atlantic headquarters.

25 October 2005

Wilma becomes an extratropical monster...

After thrashing southern Florida, Wilma quickly moved up along the 
coast, interacting with the deep trough to its west and associated 
mid-latitude Low.   The damage from Wilma in Mexico and the US combined 
is incredible, probably in the $15 billion ballpark, one of the 
costliest hurricanes (certainly behind Katrina and Andrew though).  
There are still 10s of thousands of tourists left stranded in terrible 
conditions in Cancun and Cozumel, and many millions of people in Florida 
without power, perhaps for a few weeks.

The final advisory was written at 21Z today on Wilma, with sustained 
winds of 75kts and racing NE at 46kts.  It merged with the mid-latitude 
storm over the northeast US and has created a very potent hybrid 
Nor'easter.  New England and southeast Canada are experiencing some 
hefty winds, torrential rains, and crippling snow as a result.
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/wilma/prog12hr.gif
http://www.rap.ucar.edu/weather/surface/displaySfc.php?region=car&endDate=20051025&endTime=-1&duration=0

Elsewhere, a tropical wave that exited Africa about 2 weeks ago is in 
the southwestern Caribbean Sea and showing signs of organization.  If it 
develops, it would drift northward, and the next number/name on deck is 
26/Beta.

The season's NTC is now a new record... 234.1%.  And as if breaking the 
record isn't enough... we still have 5 weeks left in this active 
hurricane season!
Please visit my tropical Atlantic headquarters.

24 October 2005

Wilma makes US landfall, Alpha dissipates...

At about 11Z this morning, Wilma made landfall as a powerful CAT3 
hurricane on Cape Romano, FL.  Upon exiting the Yucatan, it was a CAT2, 
but intensified back up to 110kts by the time it reached Florida.  
Reports are that places to the south of landfall got an 18' storm surge, 
including major surge damage in the Keys.  Also, the southern (right) 
eyewall went directly over Miami as a CAT2.  Even Havana, Cuba is under 
6' of water from Wilma.  A radar loop showing landfall in FL can be 
found at 
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/wilma/kbyx/Wilma_RadarKBYX.gif
This is the 4th major hurricane landfall on the US this year, which is a 
new record... many years have had 3 major US landfalls, but never 4, 
until now.

At 15Z, Wilma was located at 26.9N 80.0W (very near West Palm Beach) and 
tracking NE at 22kts.  A cold front and trough are right on its heels so 
there is certainly some baroclinic interaction occurring, which means 
the extratropical transition is not far behind -- the forward speed 
indicates this as well.

Alpha was only a tropical storm for 3/4 of a day, then after crossing 
over the mountainous island of Hispaniola, it was dimished to a weak 
tropical depression, and is presently beginning to merge with Wilma's 
large circulation.  However, though Alpha was weak and short-lived, it 
did set the record for number of named storms in a season... 22.  And 
the season still has 5 weeks left!  The next few names on deck are Beta, 
Gamma, Delta, and Epsilon.  A tropical wave that left Africa on Oct 19 
is currently at about 45W and has maintained persistent convection and 
is worth keeping an eye on.

The NTC as of 15Z today is 230.3%, second only behind 2004 which was 
233% (if you count STS Nicole).  We have surpassed the mega years of 
1933, 1995, 1926, and 1950.
Please visit my tropical Atlantic headquarters.

22 October 2005

Wilma STILL pounding the Yucatan, and TS Alpha forms...

Since Friday morning, Cozumel, Cancun, and the entire tip of the Yucatan peninsula have been pummeled by a major hurricane, including 100-130mph sustained winds and over 5 FEET of rain.  This could be a catastrophic blow to these populated resort areas.  Once again, the latest radar image from Cancun can be found at
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/wilma/latest.gif
and there is a growing (now pretty large) radar loop at http://einstein.atmos.colostate.edu/~mcnoldy/tropics/wilma/Wilma_Radar.gif
The radar imagery still shows a very well-defined and large eyewall 75 miles across.

Wilma is now located right on the northern coast of the Yucatan and creeping north at 2kts.  Intensity is down to 85kts and 957mb.  As it drifts off the coast and enters the Gulf, it could re-intensify a bit.
The hurricane force winds extend out 75 miles from the center, and tropical storm force winds extend out about 160 miles from the center. A Hurricane Watch has been issued for all of southern Florida, basically south of Tampa and Cape Canaveral.  US landfall is expected midday Monday as a CAT2 hurricane near Fort Myers.  The Florida Keys are under a mandatory evacuation as well.

This morning at 15Z, the first advisory was written on TD25, which formed in the eastern Caribbean.  Even more amazing is that this came from an African wave about 10-11 days ago.  Then at 21Z, it was upgraded to Tropical Storm Alpha, the 22nd named storm of the season.  This now sets the record for the highest number of named storms ever in the Atlantic.  The plan in place was to use the Greek alpha bet once the English alphabet is used up (and only 21 of 26 letters are used).

It has become much better organized throughout the day, showing healthy banding features and outflow.  It is just a few miles south of the Dominican Republic and is headed north toward it, hindering any chances for development, but still will cause heavy rain thoughout Hispaniola. A Tropical Storm Warning is in place for Hispaniola and the eastern Bahama islands.  The forecast is to head north then northeast into the open ocean, and probably not making it to hurricane intensity.

Please visit my tropical Atlantic headquarters.

21 October 2005

Wilma pounds Yucatan...

Wilma remained on course for a direct hit on Cozumel and Cancun, and has 
unfortunately almost stalled there.  The island of Cozumel has been in 
the eyewall for much of the afternoon.  Again, you can find the latest 
radar image from Cancun at 
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/wilma/latest.gif 
and if you're interested in watching a long and growing radar loop, 
that's available at 
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/wilma/Wilma_Radar.gif

Aircraft have been flying it all day, and the pressure has remained 
steady in the mid 920mb ballpark.  The eyewall has contracted slightly 
during the day, now down to 24 miles across.  Sustained winds are 120kts 
with gusts to 145kts.  The cirrent location is directly over Cozumel.

The forecast is pretty bad for Mexico... the storm is expected to stall 
over the Yucatan peninsula for a couple of days, then with the next 
trough, get pushed ENE toward southern FL.  US landfall is now forecast 
to be Monday afternoon near Fort Myers as a CAT2 hurricane.  The 
intensity forecast is VERY iffy at this point, so FL residents should 
prepare for much worse and hope for the best.  Wilma is already 
responsible for at least 13 deaths.
Please visit my tropical Atlantic headquarters.

20 October 2005

Wilma taking aim at the Yucatan...

The mighty Wilma has undergone an eyewall replacement cycle, meaning 
that the once tiny eyewall of yesterday has been replaced by a larger 
one.  This process typically weakens a storm a bit, but leaves room for 
further strengthening.  I think of it like a hermit crab leaving a shell 
it has outgrown and crawling into a new one... very vulnerable during 
the exchange, but has room to grow afterward.

The latest intensity as measured by aircraft is 130kts and 918mb, a very 
powerful CAT4 storm.  The area of hurricane-force winds is expanding 
too, now extending 75 miles from the center.  The aircraft pressure 
fixes, as well as eye diameters, are plotted at 
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/wilma/Wilma_Recon.png 
current as of Thursday afternoon.  I am generating an auto-updating 
radar loop from Cancun, available at 
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/wilma/Wilma_Radar.gif.  
A new image is added to the loop roughly every 30 minutes, so just 
refresh your browser if it's old.  Mexican radars are sometimes turned 
off at night, so there may not be any current images for several hours 
(hopefully that's not the case tonight).

The forecasts have consistently been too far north and too fast.  It is 
still creeping toward the Cancun/Cozumel area, and should directly hit 
them tomorrow afternoon as a very powerful and large CAT4 or even CAT5 
hurricane.  To make matters worse, the trough responsible for turning 
the storm northward might not be deep enough to whisk Wilma away, 
leaving it to almost stall over the Yucatan peninsula for a couple days.  
Cuba, Cancun, and Cozumel are all evacuating people, and Florida is 
about to start.

A Hurricane Watch is in effect for the northwest Yucatan peninsula and 
for all of western Cuba.  A Hurricane Warning is in effect for the rest 
of the Yucatan peninsula and Cozumel.  This is a potentially 
catastrophic storm for these resort areas who were already hit hard by 
CAT4 Emily just 3 months ago.  Thankfully, with this slower speed comes 
longer preparation times in Florida.  The southern tip of FL is now 
forecast to be hit Monday morning by a major hurricane, perhaps in the 
same area where Charley hit last year as a CAT4. The Keys are also 
especially vulnerable and in the strike zone.  As coastal residents 
often say... "it's the price we pay for living in paradise".
 
 
Please visit my tropical Atlantic headquarters.

19 October 2005

New record low pressure in the Atlantic...

Wilma has very quickly become a storm for the history books.  At 21Z 
yesterday, the winds were 70kts and the MSLP was 970mb.  It then 
intensified at rates never before seen, bottoming out at 882mb early 
this morning, a new record low pressure (beat Gilbert's 888mb in 1988) 
for the Atlantic.  MSLP fell almost 100mb in 24 hours, and over 60mb in 
just 6 hours!  

Since this morning, the central pressure has held steady at 892mb, and 
an eyewall replacement cycle is beginning, which will weaken it a bit, 
but leave room for future strengthening.  You can view a plot of central 
pressures observed by aircraft at 
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/wilma/Wilma_Recon.png 
(it comes with a humor warning).  The environment continues to be 
flawless for it, and the oceanic heat content will actually INCREASE in 
the coming couple of days.  
http://www.aoml.noaa.gov/phod/cyclone/data/ca.html

At 21Z today, the maximum sustained winds are 140kts and the MSLP is 
892mb -- located at 17.7N 83.7W and tracking WNW at 6kts.  The truly 
remarkable feature is the VERY tiny eye.  The diameter has been as small 
as 2 nautical miles, now at about 5.  This pinhole eye is largely 
responsible for allowing the storm to acquire and maintain such a low 
pressure.

The intensity forecast is basically to remain a CAT4/5 storm as it 
heads toward the Yucatan peninsula.  Cancun and Cozumel are in serious 
danger.  Then if it tracks over land it would obviously weaken quite a 
bit, or if it manages to cross through the Yucatan Channel it would 
weaken only slightly owing to increasing shear and decreasing heat 
content.

However, the track forecast is perplexing.  Model agreement is very 
good in taking it through the Yucatan Channel then recurving into the 
FL peninsula.  However, the northward nudge that has been forecast is 
not happening so far, so how much longer will it resist moving 
northward?  The official forecast does recurve it, making landfall near 
Fort Myers, FL Sunday morning as a major hurricane.
Please visit my tropical Atlantic headquarters.

18 October 2005

Wilma becomes a hurricane...

At 15Z today, Wilma was upgraded to the 12th hurricane of the season 
based on aircraft data.  At 21Z, Wilma was located at 16.7N 81.5W (180 
miles south of the Cayman Islands) and tracking WNW at 7kts.  Intensity 
measured by aircraft is 70kts and 970mb, and further strengthening is 
expected, perhaps becoming the 6th major hurricane of the season 
Wednesday evening-ish.  The central pressure has fallen 19mb in the past 
24 hours, and 10mb in the past 6 hours.  All factors point to rapid 
intensification (cold cloudtop persistence, low vertical shear, SSTs in 
the 28.5-29C range, high low-level humidity, large oceanic heat 
content).  Recall that this is the same time of year and same part of 
the Caribbean where Mitch formed and became very intense back in 1998.

The forecast is for continuing to the northwest then a more abrupt turn 
to the northeast in response to a mid-latitude trough moving in, 
threading between Cuba and the Yucatan.  This should steer the storm 
into the western FL peninsula sometime over the weekend, likely as a 
major hurricane (perhaps the Naples area).  The fetch will be large too, 
allowing huge waves (40-60 feet) to travel toward the FL coast on the 
right side of the storm motion.

Hurricane Watches are now in effect for western Cuba, eastern Yucatan 
Peninsula, and Tropical Storm Warnings are in place for the eastern 
portion of the Hinduras coast, and for the Cayman Islands.  You can 
track the storm via radar as it nears Cancun at 
http://smn.cna.gob.mx/radares/rad-canc.jpg

The NTC as of 21Z today is 202%, in 7th place for all seasons since 1900.
Please visit my tropical Atlantic headquarters.

17 October 2005

Update on Atlantic Earliest "N-th" Tropical Storm Stats

From Gary Padgett:

Now with the naming of TS Wilma, the Atlantic has tied its
current record for tropical storms/hurricanes.   Every storm
from Dennis through Wilma, except for Lee (12th) and
Stan (18th) set a new record for earliest date of its rank.

Following is a list of the earliest dates of Atlantic storms
#1 through #21 (not counting subtropical storms).  This
is based upon the current Best Track---things could get
changed in the re-analysis.   For the storm rank in which
2005 storms set a new early record, the previous
record holder is indicated in parentheses following.

Storm #           Earliest Date
-----------------------------------------------------------------------------------
    1                 2 Feb 1952   (See Note)
    2                17 May 1887
    3                12 Jun 1887
    4                 5 Jul 2005 - Dennis      (7 Jul 1959 - Cindy)
    5                12 Jul 2005 - Emily       (23 Jul 1959 - Debra)
    6                22 Jul 2005 - Franklin    (4 Aug 1936)
    7                24 Jul 2005 - Gert         (7 Aug 1936)
    8                 3 Aug 2005 - Harvey     (15 Aug 1936)
    9                 7 Aug 2005 - Irene        (20 Aug 1936)
  10                22 Aug 2005 - Jose        (23 Aug 1995 - Jerry)
  11                24 Aug 2005 - Katrina     (28 Aug 1933)
  12                29 Aug 1995 - Luis
  13                  2 Sep 2005 - Maria       (8 Sep 1933)
  14                  6 Sep 2005 - Nate        (10 Sep 1933)
  15                  7 Sep 2005 - Ophelia    (16 Sep 1933)
  16                18 Sep 2005 - Philippe    (27 Sep 1933)
  17                18 Sep 2005 - Rita          (28 Sep 1933)
  18                  1 Oct 1933
  19                  5 Oct 2005 - Tammy     (25 Oct 1933)
  20                  9 Oct 2005 - Vince        (26 Oct 1933)
  21                 17 Oct 2005 - Wilma      (15 Nov 1933)

Note: Hurricane Alice was named on 2 Jan 1955, but the system originated
in late Dec, 1954, and is now counted as a 1954 storm.   There was a
subtropical storm in Jan, 1978, but this is not counted here.


Please visit my tropical Atlantic headquarters.

TD24 upgraded to TS Wilma...

Over the weekend, TD24 has remained stationary for the most part, with a 
slight southwest drift during Sunday night.  The convection has 
gradually increased and is over the center of circulation.  At 09Z 
today, it was upgraded to the 21st named storm of the season, Wilma, and 
2005 is now tied with 1933 for the highest number of named storms.

At 18Z, Wilma was located at 16.1N 80.0W (halfway between Jamaica and 
Honduras) and creeping southward.  A westward drift is expected to 
commence today.  Intensity estimated by satellite methods is 40kts and 
997mb.  An aircraft will be in the storm later today for a more accurate 
intensity observation.  The ocean under it is plenty warm and deep to 
sustain a strong hurricane, and the forecast reflects that, bringing it 
to nearly CAT3 strength in 5 days.  The track is EXTREMELY uncertain, 
since the steering currents are so weak and erratic right now.  Stay 
tuned to the NHC for the latest track forecasts, but keep in mind that 
the 3-5 day positions are quite uncertain.  The 15Z official forecast 
takes it over the northeast tip if the Yucatan Peninsula in 5 days, then 
entering the Gulf of Mexico as a 95kt hurricane.  ALL Gulf coast 
residents shoudl be watching this very closely, from Mexico to Florida.

As of 15Z, the seasonal NTC stands at 198%, meaning that 2005 so far has 
been about twice as active as a typical entire season.
Please visit my tropical Atlantic headquarters.

15 October 2005

TD24 forms in the western Caribbean...

This is far from a sudden development, and in fact, this area has been suspect for almost 10 days now as a long draping tail of clouds and vorticity have persisted from near Nova Scotia down to the western Caribbean in association with a monster mid-latitude upper-Low.  As sometimes happens, the trailing end can wrap up into a discreet vortex, and that's exactly what happened!  So, after much festering, we finally have the 24th Tropical Depression of the season.

At 21Z today, the first advisory was written on TD24 and NHC placed it at 17.6N 78.8W with a motion of W at 2kts.  Intensity is a modest 25kts and 1004mb.  The SSTs under it are 28.5-29C and there's already a well-established anticyclone over it, minimizing wind shear and providing ample exhaust outlets.

Computer models have favored genesis for a while now, and now that it has occurred, they like it even better, bringing it up to a hurricane and even a major hurricane in a few days.  As suggested before, conditions are very favorable for this to happen.  The track will be SLOW, and primarily to the west.  Anyone from Belize to western Cuba should be watching this VERY closely.

If this gets named, its will be Wilma, and we will tie 1933 with the highest number of named storms (21).

Please visit my tropical Atlantic headquarters.

10 October 2005

STD22 and Vince form...

Over the weekend, for a brief period (less than a day), Subtropical 
Depression 22 could be found southeast of Bermuda, racing toward it, 
but being sheared apart as it moved.  It quickly lost tropical 
characteristics and never reached STS or TS status.

Also over the weekend, TS Vince formed in the FAR eastern part of the 
basin, and is now located at 34.9N 14.2W, or just off the coast of 
Morocco (never thought I'd be typing those words!) and heading toward 
Portugal.  Intesity estimates are 40kts and 1002mb.  For 1/2 day, it 
was at minimal hurricane intensity, becoming the season's 11th 
hurricane, based on satellite imagery showing an eye in the storm.  It 
is being sheared now, and moving quickly to the ENE - it should be 
dissipated by the end of the day.

This brings the season's NTC up to 196%, which is tied with the entire 
1916 season, and leaves us behind just six other years since 1900.
Please visit my tropical Atlantic headquarters.

05 October 2005

Stan leaves a deadly wake, Tammy forms near Florida...

Stan is now responsible for 66 deaths in Mexico, Nicaragua, Honduras, Guatemala, Costa Rica, and El Salvador, all due to flooding and landslides.  The center of circulation passed over the high mountains to the west of the Isthmus of Tehuanepec and the remnants are still causing tremendous flooding.  The storm made landfall 24 hours sooner than forecast and seemingly took many people by surprise, although roughly 60,000 did have time to evacuate vulnerable areas throughout Central America.  With some speculation, it looks like the remnants of Stan have crossed into the East Pacific, south of Mexico, and are flaring back up.  If it reforms there, I believe it will be named Pilar.

Shortly after 11Z this morning, NHC upgraded the area of disturbed weather off the Florida coast to TS Tammy, the 19th named storm of the season.  This ties the named storm count from 1995, but is still behind the 1933 count of 21.  As of 15Z, the center of this highly-sheared storm was located at 28.9N 80.3W and tracking N at 12kts.  Intensity estimated from buoys and radar is 35kts and 1004mb.  Only slight strengthening is forecast before landfall somewhere near the FL/GA border late tonight.  For the latest warnings, check http://www.nhc.noaa.gov/refresh/graphics_at1+shtml/143914.shtml?3day and to track the storm via radar, check http://www.srh.noaa.gov/radar/latest/DS.p20-r/si.kjax.shtml

Also, there is a VERY impressive blowup of deep convection just east of the Yucatan Peninsula, basically where Stan formed.  One can see a mid-level circulation in the visible satellite imagery as well as healthy outflow aloft.  This has not been mentioned by NHC or picked up by the models, but it bears watching.

Please visit my tropical Atlantic headquarters.

04 October 2005

TD19 forms and dissipates, Stan hits Mexico...

Since my last update on 26 Sept, two Depressions have formed, one of 
which became a hurricane.  TD19 was the easternmost formation of the 
season, all the way out at 33W, but was only around for 2 days before 
getting ripped apart by increasing vertical wind shear.  The final 
advisory was written on it on Sunday afternoon.

TD20 formed on Saturday afternoon just east of the Yucatan Peninsula.  
It was upgraded to TS Stan, the 18th named storm of the season, just 
prior to landfall there, and only weakened slightly as it crossed the 
peninsula.  Upon exiting, it very quickly flared back up and became the 
10th hurricane of the season early Tuesday morning.  It traveled quickly 
across the warm Bay of Campeche and made landfall mid-morning on Tuesday 
as a CAT1 storm near Alvarado in the state of Veracruz.

Elsewhere, there is a large and persistant area of disturbed weather 
over the Bahamas.  A 1006mb Low is embedded within the broad 
circulation, but is also in an area of unfavorable wind shear.  Most 
models predict that this shear will lessen, giving the storm a chance 
to organize.  It is forecast to continue tracking WNW across FL and 
enter the Gulf by midday Wednesday.  This will be monitored very closely 
by satellite and eventually by aircraft as the system moves westward 
toward Florida.  If it does develop, the next number/name on deck is 
21/Tammy.

The NTC for the season stands at 189%, the 10th highest value since 
1900, and the season is still going.
Please visit my tropical Atlantic headquarters.

26 September 2005

Rita makes landfall...

In the early morning hours on Saturday (around 3am local), Rita crossed the coastline as a powerful Category 3 hurricane, near Sabine, TX on the TX/LA border.  Cameron, LA got the eastern eyewall and was severely damaged, as was Lake Charles, LA.
You can view a radar loop that I made of this landfall at http://einstein.atmos.colostate.edu/~mcnoldy/tropics/rita/Rita_23-24Sep05.gif

Also, photojournalist Allan Detrich recorded a sound file during the eyewall passage in Beaumont, TX... you can listen to this short clip at http://einstein.atmos.colostate.edu/~mcnoldy/tropics/rita/rita.WAV.  In terms of rainfall, New Orleans got 6.3", Beaumont received about 9"; Center, TX got 10.5"; and the largest total is in Bunkie, LA at 16".

Elsewhere, nothing is of immediate concern as shear seems to dominate many of the classic formation zones.  However, there are active waves out there, so if conditions improve, something could form fairly quickly.

Please visit my tropical Atlantic headquarters.

23 September 2005

Rita less than 24 hours from the coast...

At 15Z, Rita was located at 27.4N 91.9W, about 200 miles from Sabine TX.  Aircraft-measured intensity is 115kts and 929mb.  It is in the midst of an eyewall replacement cycle, so the intensity may fluctuate +/- 10-15 kts.   Hurricane Warnings are in effect from Port O'Connor TX eastward to Morgan City LA.

Landfall is still expected to occur between Galveston TX and Cameron LA, perhaps near the small coastal town of Sabine TX.  Intensity is a great forecast problem, but should be CAT 3/4 barring any unforeseen changes.  The majority of hurricane conditions leading up to landfall will occur during the early morning hours on Saturday, then landfall itself should be around sunrise-ish.  Hurricane-force winds will be felt about 85 miles to the east and west of the landfall point, including Houston and Lake Charles.  The following map shows the potential storm surge from Rita:  http://www.fema.gov/hltdata/attachments/u1_sabine_slosh.jpg

My friend and photojournalist Allan Detrich is in Beaumont TX with reporter Dennis Roddy from the Pittsburgh Post-Gazette.  They are at the Civic Center there, and report that the city is a ghost town, barely anyone to be seen, gas is very hard to come by, and winds are ~15mph and picking up slowly.  Sites along the coast are already seeing water levels rise several feet: this site shows the tidal gauge data from Sabine, TX, which is right on the coast at the TX/LA state border.
http://tidesonline.nos.noaa.gov/plotcomp.shtml?station_info=8770570+Sabine+Pass+North,+TX+&flag=0

You can also follow the storm via the Lake Charles radar at http://radar.weather.gov/radar/latest/DS.p20-r/si.klch.shtml or via the Houston radar at http://radar.weather.gov/radar/latest/DS.p20-r/si.khgx.shtml

Part 2 of issues with Rita is that the steering flow is forecast to be basically non-existant once it's inland a bit, leaving it to rain for days over TX/LA/AR/OK... possibly dumping over 2 FEET of rain.  And of course, the usual threat of tornadoes exists associated with the hurricane.

Philippe is STILL hanging on as a tropical storm, barely recognizable as a tropical entity.  As of 15Z today, it was located at 31.1N 63.2W (just southeast of Bermuda) and the estimated intensity was 35kts and 1005mb.  It is heading north, and has prompted Bermuda to issue a Tropical Storm Warning.

Elsewhere, something that spun off of Philippe is presently halfway between Bermuda and Puerto Rico and could be worth watching over the next few days.  Also, a large tropical wave that exited Africa yesterday morning is located at about 12N 28W and bears watching... although the vertical shear is VERY high over it now, the low-level energy should persist and could develop when conditions improve.

Please visit my tropical Atlantic headquarters.

22 September 2005

Rita breaks the 900 barrier...

At 03Z today, Hurricane Rita's central pressure bottomed out at 897mb, nudging past the rarely-broken 900mb threshold.  Only 3 other storms have achieved this intensity: Gilbert 1988 (888mb), Labor Day 1935 (892mb), and Allen 1980 (899mb).  This occurred just 24 days after Katrina reached its peak intensity of 902mb, and virtually at the same location.

Since then the storm has weakened a BIT, and is presently at 915mb and ~140kts.  Given that such a high intensity is so hard to achieve, let alone maintain, the storm is expected to weaken further over the next 24-36 hours prior to landfall.  BUT, keep in mind that a storm at 907mb has a looong way to weaken before it's not major, so landfall will almost certainly be as a CAT3/4 hurricane.  It's moving WNW at 8kts, but this motion will become NW with time as the steering ridge to its north shifts eastward.  The latest position is 25.4N 88.7W, or about 225 miles due south of the mouth of the Mississippi River.

Landfall is becoming a more ominous event, and is expected to occur in the early morning hours on Saturday as a major hurricane.  The latest official track forecast and model guidance have shifted eastward a bit, now placing the prime target just east of Galveston Bay.  Hurricane Warnings are in place now from Matagorda Bay TX eastward to Atchafalaya Bay LA, and evacuations are underway in many cities within the warning area (also in New Orleans with fears of the rainfall breaking the patched levees).  Hurricane-force winds now extend 75 miles from the center.

Looking beyond landfall, the steering flow is forecast to dwindle, leaving Rita to stall over TX/OK/AR/LA, perhaps dumping upwards of 2 feet of rain over the area.  This has to potential to be a very catastrophic storm.  The eyewall is only one part of the storm... the coast has to contend with a large storm surge, and places inland have to contend with rain-induced flooding and spiral band-spawned tornadoes.

Philippe is still a tropical storm, with estimated intensity at 35kts and 1005mb.  It is quickly losing tropical characteristics and today will likely be its last day as a tropical system.  The transitioning system is heading north toward the north-central Atlantic.

The season's NTC stands at 175% now; only ten years since 1900 have had higher seasonal NTCs, and this season isn't over yet.

Please visit my tropical Atlantic headquarters.

21 September 2005

Rita reaches Category 5 intensity...

Hurricane Rita has been very well observed by aircraft today, having four planes in it simultaneously at times.  And based on the data collected by the planes, Rita was upgraded to a CAT5 hurricane at the 21Z advisory today.   The maximum sustained winds are 145kts (maybe higher now?) and the central pressure has plumetted to 904mb and still falling.  This is a big storm, with hurricane-force winds extending 50 miles from the center... this will only grow with time.

Landfall is of course the big concern with this storm (otherwise, it would just be a beautiful vortex over the open ocean!).  Computer model guidance has gradually clustered more around the Port Lavaca area, or roughly halfway between Corpus Christi and Galveston/Houston.  The timing should place Rita near the coast late Friday night into early Saturday morning.  A Hurricane Watch has just been issued for basically the entire TX coast, and evacuations are well underway in Houston, Galveston, Corpus Christi, Port Lavaca, and other smaller towns in between.  A worst-case scenario that people are preparing for is that the storm comes in just south of Galveston, driving Galveston Bay into parts of Houston.

Please visit my tropical Atlantic headquarters.

Rita intensifies very quickly, headed for Texas...

Phillipe has weakened to a tropical storm and will likely struggle to 
maintain that status as it's pounded by strong westerly wind shear.  
It's located  northeast of the Leeward Islands and barely looks tropical
anymore.  Latest intensity estimate is 45kts and 1000mb.

Rita, on the other hand, has strengthened immensely since my last update 
on Monday afternoon.  It became the 9th hurricane of the season on 
Tuesday morning, and continued to strengthen rapidly as it became the 
5th major hurricane of the season early Wednesday morning.  This trend 
continues, and Rita is nearly a CAT5 hurricane now.  The latest central 
pressure as of this writing is 920mb, which means the pressure has 
fallen 28mb in the last 6 hours, and 58mb in the last 24 hours.  One 
wonders how much further it will fall, and will it exceed Katrina's peak 
intensity of 902mb?

It is about to pass over a deep warm eddy in the central Gulf, which 
should give it another boost in intensity.  Then ~12 hours after that, 
it MIGHT pass over a cool eddy and could weaken the storm a bit.  Keep 
in mind the surface temperature of the water is still a toasty 
28.0-29.5C along its projected track, but the DEPTH of that warm water 
can play a role too.
http://www.aoml.noaa.gov/phod/dataphod1/work/HHP/NEW/2005263go.jpg

The last official advisory at 15Z had the intensity at 120kts and 944mb, 
but that is already far too weak.  The motion is toward the W at 11kts, 
and environmental conditions are ideal for further strengthening.  The 
forecast calls for the hurricane to maintain CAT4/5 intensity through 
landfall, which raises the age-old questions of when and where.  
Landfall is expected to occur in the early morning hours on Saturday, 
roughly halfway between Galveston/Houston and Corpus Christi, or near 
Port Lavaca.  Although Hurricane Watches are not yet posted for the TX 
coast, mandatory evacuations are already being carried out in the areas 
I just mentioned, particularly vulnerable Galveston and populated 
Houston.  Hurricane Katrina refugees who moved from one costal city to 
another coastal city in the peak of hurricane season are being moved 
again out of harm's way (not a big surprise).  This time, the evacuees 
are moving inland.
Please visit my tropical Atlantic headquarters.

19 September 2005

Philippe and Rita both strengthening...

Philippe was upgraded to a hurricane -- the 9th of the season -- at 03Z 
today based on satellite presentation.  It is a minimal hurricane with 
65kt sustained winds, but it is forecast to intensify, perhaps reaching 
CAT3 status in a few days.  The good news is that it is in the central 
Atlantic and will remain there, heading north.  At 15Z, it was located 
at 17.4N 56.3W, or about 5 degrees east of the Leeward Islands.

TD18 was upgraded to TS Rita at 21Z yesterday, and the storm is 
apparently starting a rapid intensification phase now, with structural 
improvements every hour.  A plane is en route as I write this and I 
suspect it will find that Rita is now a hurricane.  As of 15Z, TS Rita 
was located at 23.0N 75.2W (over Great Exuma Island in the Bahamas) and 
tracking WNW at 10kts.  The estimated intensity was 55kts and 994mb, but 
that will be updated with actual observations once the aircraft 
penetrates the storm in the near future.  The SSTs in the storm's 
immediate path are very warm, 30C+, with a strong ridge to the north 
providing minimal wind shear and westward steering flow.

More and more computer models favor a major hurricane hitting the 
Florida Keys on Tuesday afternoon/evening, which would be devastating, 
since mandatory evacuations have only begun this morning.  Furthermore, 
the storm will then enter the Gulf of Mexico and has no obvious factors 
to keep it from becoming even stronger.  As of now, the landfall 
position is anywhere from the central TX coast eastward to eastern LA, 
and although intensity is not accurately known out that far, it should 
be rather strong.  This landfall on the Gulf Coast is expected to occur 
late Friday into early Saturday, depending on the exact track.

A Hurricane Warning is in place for some of northwestern Cuba, Andros 
Island in the Bahamas, and all of the southern tip of Florida.  
Mandatory evacuation orders are in place for the Florida Keys, and 
voluntary evacuations are occuring further north toward Miami.
http://www.nhc.noaa.gov/refresh/graphics_at3+shtml/153924.shtml?3day
 
 
 
Please visit my tropical Atlantic headquarters.

18 September 2005

Ophelia dissipates, Philippe and TD18 form...

Late Saturday night, the NHC wrote the final advisory on Ophelia, as she was zipping off past Newfoundland into the north central Atlantic and becoming an extratropical cyclone.

The large tropical wave I have been discussing in the central deep tropics was upgraded to TD17 on Saturday morning, and then upgraded again to TS Philippe on Saturday night.  Although forecast to become a major hurricane, it is also expected to turn to the north and recurve by 65W, never affecting land.  As of 15Z today, Philippe was located at 15.2N 55.7W and tracking NNW at 6kts.  Satellite-estimated intensity is 45kts and 1000mb.

And the area of disturbed weather I mentioned on Friday near Puerto Rico was upgraded to TD18 on Saturday night and continues to get better organized by the hour.  It is currently located at 22.0N 72.2W (over the far eastern Bahamas) and tracking W at 10kts.  The estimated intensity is 30kts and 1008mb, but aircraft recon missions are planned for it to get a better handle on actual intensity.  This should become TS Rita later today.

A Hurricane Watch is in effect for the western Bahamas and for the Florida Keys.  A Tropical Storm Warning is in effect for the eastern Bahamas.  This storm is forecast to pass between Cuba abd Florida and enter the Gulf on Wednesday as a powerful hurricane.  The latest computer model guidance shows a westward track, heading toward TX/Mexico, but all eyes should be on it anywhere along the Gulf, and certainly southern Florida.

Elsewhere, there's an area of interest in the deep tropics, near 11N 37W.  This is forecast to move westward toward the Lesser Antilles and gradually strenghten.  It's currently poorly organized, but conditions should improve.  The next number/name on deck is 19/Stan.

I should also point out that the Eastern Pacific basin presently has three named storms as well (Jova, Kenneth, and Lidia), so someone must have turned on a switch!

Please visit my tropical Atlantic headquarters.

16 September 2005

Ophelia creeping away from the US coast...

Category 1 Hurricane Ophelia pounded the NC coast for over 40 hours as 
it moved VERY slowly along the coastline.  It never actually made 
landfall, but the western eyewall remained over land the whole time.  I 
suspect we'll hear more about the flooding and coastal 
erosion/destruction in the coming days.  It's nothing like what Katrina 
did, but not negligible either.  You can view a couple of radar loops of 
the slow transit at:
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/ophelia/Ophelia_13-14Sep05.gif
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/ophelia/Ophelia_14-15Sep05.gif

Last night, Ophelia was downgraded to a tropical storm and is still 
sitting just east of the NC/VA border.  The latest intensity is 50kts 
and 996mb.  The forecast track takes it NNE, just clipping by Cape Cod 
and perhaps hitting Nova Scotia on Saturday night.

Elsewhere, that large tropical wave I mentioned a couple days ago is 
still there, moving slowly westward, and is not in any rush to get 
better organized.  It must still be watched very closely, because of the 
potential track if it develops.

And lastly, an area of disturbed weather has been festering at the 
trailing edge of an old cold front, just north of Puerto Rico.  This has 
been gradually getting better organized, but again, it's in no hurry.  
Either one of these systems could become TD17 (and TD18?) over the 
weekend.
Please visit my tropical Atlantic headquarters.

14 September 2005

Ophelia pounding the NC coast...

Hurricane Ophelia has still not technically made landfall as of 22Z, but 
the western eyewall is raking the coast, exposing every coastal 
community in NC to the eyewall for hours due to its slow motion.  Aside 
from the torrential rains which may total 20" in some places, a 10' 
storm surge can be expected in the bays of eastern NC.

As of 22Z, Ophelia was located at 34.2N 77.0W, or approximately 40 miles 
form the coast.  Keep in mind that center position is the location of 
the center of the large eye, so hurricane-force winds already can be 
found inland.  Intensity is 75kts and 979mb, with perhaps a bit more 
strengthening in the next 12-24 hours.  You can follow its progress via 
radar imagery at 
http://weather.noaa.gov/radar/latest/DS.p19r0/si.kmhx.shtml

Elsewhere, a large tropical wave that exited Africa on September 8 is 
making its way westward across the deep tropics.  Currently at about 7N 
45W, it's taking a very far south track, reminiscent of Ivan 2004.  
Conditions do appear favorable for gradual intensification, and this 
should become TD 17, and the next name on deck is Philippe.
Please visit my tropical Atlantic headquarters.

13 September 2005

Ophelia heading toward US east coast...

My last update was sent on Thursday, but very little has happened since 
then.  Maria and Nate are long gone, absorbed by a mid-latitude trough.  
Ophelia has drifted or remained stationary day after day, now heading 
NNW at 3kts toward the NC coast as a minimal hurricane.

At 21Z, Ophelia was located at 32.7N 77.9W, or about 100 miles east of 
Charleston.  Aircraft-measured intensity is 65kts and 985mb.  It should 
maintain this intensity as it scrapes the coastline and Outer Banks.  A 
Hurricane Warning is in effect for most of NC and the northern half of 
SC.  Hurricane Watches cover the remainder of NC and SC.  You can track 
the hurricane via radar at 
http://weather.noaa.gov/radar/latest/DS.p19r0/si.kltx.shtml

21 years ago today, Hurricane Diana made landfall on the NC coast.  And 
17 years ago today, the Atlantic's most intense hurricane on record 
(Gilbert) hit the Cayman Islands.  The season's NTC stands at 144.8%, 
which still leaves it as the 17th highest NTC overall since 1900.  Keep 
in mind it's only mid-September though!
Please visit my tropical Atlantic headquarters.

08 September 2005

a tropical tidbit to reflect on

"In the eye of a hurricane, you learn things other than of a scientific
nature. You feel the puniness of man and his works. If a true definition
of humility is ever written, it might well be written in the eye of a
hurricane." 

-- Edward Murrow, reporting on Hurricane Edna 1954


Please visit my tropical Atlantic headquarters.

Maria, Nate, and Ophelia are all hurricanes...

Maria stubbornly refuses to become a truly extratropical cyclone, and 
is still clinging onto hurricane status.  At 21Z, the storm was located 
at 39.5N 46.8W and moving NE at 10kts... this is uncharacteristically 
slow for such a high latitude!!  Satellite-estimated intensity is 65kts 
and 982mb.  Although it will remain a powerful cyclone, the next 1-2 
days will see the full transition from tropical to extratropical.

Nate has changed very little in the past 24 hours, but has passed to 
the south of Bermuda and is now safely out of their way.  It remains a 
CAT1 hurricane with sustained winds of 75kts and a central pressure of 
982mb.  As of 21Z, it's at 31.8N 62.0W and tracking NE at 14kts.

Ophelia, sitting at exactly the same spot it was 24 hours ago, was 
recently upgraded to a hurricane, the seventh of the season.  It is 
intensifying just dozens of miles east of Cape Canaveral, and shows no 
signs of moving soon.  However, with the warm Gulf Stream flowing 
underneath it, a constant supply of energy is available.  The latest 
intensity is 65kts and 985mb.  You can track it easily from Melbourne's 
radar at http://www.srh.noaa.gov/radar/latest/DS.p19r0/si.kmlb.shtml.  
In the near term, it is expected to gradually drift toward the NE, but 
the US coast should not let it's guard down... several models project 
that it could loop back around and hit the coast.

The season's NTC is climbing rapidly now, and stands at an impressive 
140%, high for any year, but it's only September 8!  In fact, going back 
to 1900, only 16 years have had higher NTCs for the entire season, so 
it will be interesting to see how many of those will be surpassed by 
the end of the 2005 season.
 
 
Please visit my tropical Atlantic headquarters.

07 September 2005

Maria, Nate, and Ophelia ring in the peak of the season...

Maria had briefly weakened to a Tropical Storm overnight, but jumped 
back to CAT1 status during the day, and is decidedly in the early-mid 
stages of ET transition.  At 21Z, Hurricane Maria was located at 36.9N 
50.4W and accelerating to the NE.  Satellite-estimated intensity is 
70kts and 980mb.  Advisories should cease on this storm within 24 hours 
as it's absorbed by a mid-latitude trough.

Nate has strengthened into the 6th hurricane of the season, and has a 
beautiful eye in satellite imagery.  Though only a CAT1 now, there is a 
good chance that it will reach CAT2, and possibly even CAT3 within the 
next day.  It's located just south of Bermuda, and slowly intensifying.  
Latest intensity estimate is 75kts and 979mb, but an aircraft is 
scheduled to investigate it later tonight for a true measurement.  
Nate's fate is nearly identical to Maria's... being scooped up by the 
same mid-latitude trough and becoming an extratropical cyclone.

TD16 was upgraded to TS Ophelia at 06Z today.  This beats the date for 
the earliest 15th named storm by a whopping 9 days!  If I'm not 
mistaken, that means 11 of our 15 named storms this season have set the 
new record for earliest formation date.  If Philippe forms before Sept 
27th, we'll have another to add to the record list.  This storm is 
particularly intersting because it's literally just 80 miles off the 
Florida coast!  It is basically stationary, and being subject to 
moderate southeasterly wind shear.  However, it has the warm Gulf Stream 
directly under it, and plenty of time, as it is forecast to remain 
nearly stationary for the next few days.  This is one that people from 
FL to NC need to be watching rather closely.  Current intensity is 45kts 
and 996mb.  The primary threat now is the very heavy surf being 
generated along the southeastern coast.
Please visit my tropical Atlantic headquarters.

06 September 2005

Maria, Nate, and TD16 keep the season going...

TD14 formed last Thursday, was upgraded to Maria on Friday, then had a much more productive weekend than forecasters had anticipated.  Maria became the season's 5th hurricane on Saturday morning, and the season's 4th major hurricane on Monday night.  It is currently a Category 2 storm with 85kt winds and a central pressure of 975mb, located at 33.8N 55.6W.  It is feeling the effects of an upper-level trough and will begin the extratropical transition today as it's whisked out to the north central Atlantic... the hurricane graveyard.

An upper-level Low to the west of Maria developed a surface Low and became TD15 on Monday afternoon.  It was upgraded to TS Nate late last night and is looking very impressive on satellite imagery.  Nate, like Maria, is forecast to remain well out in the Atlantic and be taken out by the same upper-level trough.  However, Bermuda has all eyes on this storm, as it could hit the island as a hurricane.  I'd image that after Fabian '03, they're not looking forward to the visit.  As of 15Z today, TS Nate was stationary at 28.7N 66.7W.  Estimated intensity is 50kts and 997mb.  Further strengthening is forecast and Nate should become the 6th hurricane of the season.  This is the earliest date for the 14th named storm, beating the old record by four days.

Lastly, a new Tropical Depression formed over northwestern Bahamas this morning... TD16.  It is expected to intensify and head toward the FL/GA coast over the next couple of days.  Residents there should be alert to this storm as it is so close to land.  Conditions appear favorable for gradual intensification, and it's expected to become TS Ophelia later today or tomorrow.  At 15Z, it was located basically over Grand Bahama Island.  It's also stationary, but should begin drifting to the NNW with time.  Tropical Storm Warnings are in place for northwest Bahamas and the central portion of Florida's east coast.

With this latest flurry of activity, the NTC for the season stands at 128%, which is quite phenomenal for Sept 6!

Please visit my tropical Atlantic headquarters.

02 September 2005

Lee dissipates, Maria forms...

Since my last update on Wednesday, Lee had quickly dissipated due to excessive vertical shear.  It is now a barely noticeable low-level swirl over the north central Atlantic.

However, that hefty tropical wave I mentioned was finally upgraded to TD14 on Thursday morning, and then upgraded to TS Maria this morning.  It will have a track and fate nearly identical to Lee, so it is no threat to land.  It is not forecast to reach hurricane intensity.  As of 15Z today, TS Maria is located at 21.3N 50.0W and tracking WNW at 8kts.  Satellite-estimated intensity is 35kts and 1007mb.

Maria is the earliest 13th named storm on record, crushing the old record by 6 days.  So far, every storm from Dennis through Maria has broken the record for earliest N-th storm, with the exception of Lee, who lagged Luis 1995 by two days.  If Nate forms before September 10, it will also hold the record for the earliest 14th named storm.  The season's NTC is now at 112% as of 15Z this morning, and we're just now entering the climatological peak of the season.

The wave that had just exited Africa on Wednesday has continued to trek westward and is presently near 7N 38W.  It's presently lacking deep convection, but the wave is holding together and actually has a 1008mb Low embedded within it.  The longer range track would take it very near the Leeward Islands in 5 days.  The SSTs should be at least 29C, and variable wind shear will allow for periods of strengthening and weakening, but given the overall current and future conditions, it should be free to intensify to a powerful hurricane by early next week, if not sooner.  This will likely become TD15, then the next name on deck is Nate.  This is the type of track that the US east coast needs to be on alert for.


Please visit my tropical Atlantic headquarters.

31 August 2005

Lee forms in the central Atlantic...

TD13 has regenerated and was upgraded to TS Lee today at 21Z.  However, it does not look very healthy and will likely be back down to a TD in 2-3 days.  It's located at 30.5N 49.7W and heading NNE at 12kts.  The intensity estimated by satellite is 35kts and 1007mb.

The strong tropical wave 1200 miles east of the Lesser Antilles is STILL looking impressive, with an obvious surface circulation and persistent deep convection.  This is the wave that exited Africa on August 27.  I honestly don't know why this is not being classified as TD14 yet, but from my experience, it should be.  It's presently at about 19N 42W and heading NW at 10kts.  The next name on deck is Maria.

And lastly, a new tropical wave has exited Africa and is already showing signs of a broad circulation.  This will be watched closely for signs of development over the next few days.

The NTC as of the end of the month is now 110.2%, compared to a normal 31% or so for this date.  Recall that a value of 100% corresponds to an entire average season.  So 2005 is already 10% above an entire normal season, and the climatologically active part of the season is still ahead of us.


Please visit my tropical Atlantic headquarters.

30 August 2005

Katrina still devastating parts of the coast...

36 hours after landfall, the people in New Orleans emergency shelters 
are being evacuated as levee after levee is breached by flood waters and 
the shelters are filling with water.  Water from the Mississippi River 
and from Lake Pontchartrain is now pouring into the city, bringing the 
water level up to at least 25 feet in parts of the city.  Also, as time 
goes by, we start to get more reports from the coast of Mississippi and 
realize how complete and extensive the destruction really is.  Gulfport 
and Biloxi are in very bad shape to say the least, and strong tornadoes 
generated by Katrina's spiral bands have ravaged parts of Georgia.  This 
is very similar to Hurricane Camille in 1969, but Katrina was LARGER.

The death toll from the storm is now around 70, but there are a LOT of 
people unaccounted for, so that number could rise drastically in the 
coming days and weeks.  Nearly all communication and transportation is 
cut off, so information out of the area and assistance into the area are 
greatly hindered.   I'll once again provide a link to the American Red 
Cross for donations: https://www.redcross.org/donate/donation-form.asp.  

Although Gulfport was hit very hard by the eastern eyewall, New Orleans 
may end up being the worst off, as the city sits submerged for weeks or 
even months without power, water, or sewer services.  The ultimate 
doomsday forecast that was made for the city has sadly come to fruition.

The terrorist attacks on the US in 2001 had a total cost of about $40 
billion.  Hurricane Andrew in 1992 cost $42 billion.  All four big 
hurricanes in 2004 (Charley, Frances, Jeanne, and Ivan) added up to 
about $46 billion.  Hurricane Katrina could potentially be twice those 
values.

For those who are interested, I have created radar loops of Katrina's 
two landfalls: the first on Thursday afternoon near Miami, and the 
second on Monday morning near New Orleans.
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/katrina/Katrina_25Aug05.gif
http://einstein.atmos.colostate.edu/~mcnoldy/tropics/katrina/Katrina_29Aug05.gif

The tropical wave I mentioned yesterday over the central Atlantic 
between Africa and the Lesser Antilles has remained unchanged.  There is 
still a disorganized broad surface circulation and a more impressive 
anticyclone aloft.  It's located roughly at 14N 38W and tracking W at 
10kts.  Conditions still appear favorable for gradual development.
Please visit my tropical Atlantic headquarters.

29 August 2005

Katrina hits coastal LA and MS hard...

At about 11Z today, Katrina made landfall on the Mississippi River delta 
in southeast LA as a potent CAT4 hurricane.  Maximum sustained winds 
were estimated to be 120kts with a MSLP of 920mb.  Then it proceded 
north... the western eyewall hitting New Orleans, and the eastern 
eyewall hitting Gulfport and Biloxi.  There are already reports of 
significant flooding and damage all along the coast in LA, MS, and AL -- 
from New Orleans to Pensacola.  It's still too early to get a complete 
picture of what has transpired this morning, but it will be an extremely 
costly disaster.  Cities as far east as Mobile, AL had levees topped and 
flood waters racing into the city.  Buoys just offshore reported waves 
of 40+ ft ahead of the storm.

The storm has since moved inland and weakened to a CAT1 hurricane as of 
this writing.  Further weakening will occur, but now the primary threat 
is from inland flooding, and that is a risk for the next several days in 
the southeast and Ohio Valley.  Visit 
http://www.spc.noaa.gov/products/wwa/ to check out the most current 
watches and warnings.  Remember that tornadoes and flash floods are big 
dangers from hurricanes that have made landfall... even quite far from 
where it made landfall.

As of 19Z, Hurricane Katrina was located at 31.4N 89.6W (near 
Hattiesburg, MS) and tracking N at 15kts.  The intensity is 80kts and 
the MSLP is 955mb.  On its forecast track, it will be passing over TN, 
KY, and OH over the next couple of days.

If you wish to help the Katrina victims, the American Red Cross has a 
donation form at https://www.redcross.org/donate/donation-form.asp

Due to excessive shear in the critical formative stage, TD13 has 
dissipated into an open wave and is no longer forecast to intensify.  It 
will be watched for signs of regeneration though.  However, a relatively 
new wave has exited the African coast and is located near 10N 32W, just 
southwest of the Cape Verde Islands.  It shows signs of development and 
conditions should be favorable for gradual organization.
Please visit my tropical Atlantic headquarters.

28 August 2005

Katrina catastrophe imminent...

Since my last update on Friday, Katrina has done the unimaginable, and 
rapidly intensified to a monstrous Category 5 hurricane right off the US 
coast.  To make matters more dire, it is headed for one of the most 
vulnerable cities in the US: New Orleans.

The storm experienced a phenomenal period of rapid intensification, with 
pressure drops of 27 mb/3hr and 36 mb/12hr.  As of this writing, the 
storm is STILL strengthening, currently holding the 4th lowest pressure 
ever recorded in the Atlantic.  As of 21Z today, aircraft recon found 
maximum sustained winds of 145kts and a minimum central pressure of 
902mb.  It is located at 26.9N 89.0W and tracking NW at 10kts.  This 
puts it 225 miles south of New Orleans.  It is forecast to gradually 
turn more to the north and maintain CAT 4/5 intensity, with fluctuations 
primarily due to concentric eyewall cycles.  The best estimate for time 
of landfall is around 5am CDT on Monday.  As an aside, this makes the 
first time there have been 3 CAT5s in 3 consecutive years (Isabel '03, 
Ivan '04, and Katrina '05).

A mandatory evacuation has been ordered for all of New Orleans, as well 
as some other coastal cities in LA and MS.  The storm surge from this 
hurricane could reach 25-30 feet, with wind gusts to 200mph or even 
higher.  I wanted to share an excerpt from the forecast discussion out 
of the New Orleans NWS office: 
"MOST OF THE AREA WILL BE UNINHABITABLE FOR WEEKS...PERHAPS LONGER. 
AT LEAST ONE HALF OF WELL CONSTRUCTED HOMES WILL HAVE ROOF AND WALL 
FAILURE. ALL GABLED ROOFS WILL FAIL...LEAVING THOSE HOMES SEVERELY 
DAMAGED OR DESTROYED.  POWER OUTAGES WILL LAST FOR WEEKS...AS MOST 
POWER POLES WILL BE DOWN AND TRANSFORMERS DESTROYED.  WATER SHORTAGES 
WILL MAKE HUMAN SUFFERING INCREDIBLE BY MODERN STANDARDS." 


The President has already declared Lousiana and Mississippi 
federal disaster areas to expedite funding and recovery efforts once the storm 
passes.  A Hurricane Warning is in effect from western LA to the FL panhandle.  
Aside from the devastating eyewall, areas to the east of landfall can expect 
VERY large waves, perhaps upwards of 40 feet, along with 1-2 feet of rain.

Elsewhere, TD13 has formed from the area of disturbed weather in the deep 
tropics between the Lesser Antilles and Africa.  It is located at 15.4N 
46.8W.  Initial intensity is estimated to be 25kts and 1007mb.  This is 
from a wave that exited Africa on August 25.  The longer range forecast 
for this is to head northwest (north of the Leeward Islands) and 
gradually strengthen to hurricane intensity by later this week.  This 
should be upgraded to TS Lee sometime tomorrow.
 
 


Please visit my tropical Atlantic headquarters.

26 August 2005

Katrina slams southern FL and intensifying...

At about 23Z yesterday, Katrina made landfall as a CAT1 hurricane on 
North Miami Beach, FL.  The storm was highly asymmetric, and nearly all 
of the rainfall occurred on the south side, quite extreme in some 
places.  Wind gusts to nearly 85kts were observed at several places, and 
radar-estimated rainfall totals in southern FL are 10-20" along the 
south side of the track.  So far, this hurricane has killed 4 people, 
and left 5 missing at sea.

The hurricane barely noticed that it was over land, since the land is 
flat and mostly swampy.  Then, a peculiar turn to the southwest allowed 
the storm to spend just 7 hours over the peninsula before exiting into 
the Gulf.  It responded well to the transition and is now strengthening 
very quickly.  The pressure at first landfall was 985mb, and shortly 
after landfall was 971mb (usually is the other way around!).  Conditions 
over the Gulf are ideal for rapid intensification -- the SSTs will 
remain above 30C and the northerly shear that has been affecting it is 
expected to relax.

At 15Z today, the center of Hurricane Katrina was located at 25.1N 82.2W 
and crawling W at 6kts.  Intensity measured by aircraft is 85kts and 
971mb, making it a CAT2 storm.  The forecast is for continued 
strengthening, reaching at least CAT3 by the end of the weekend, and 
then hitting the FL panhandle (perhaps between Pensacola and Panama 
City) on Monday morning.  Ahh, the Sunshine State...

Elsewhere, the same circulation and area of disturbed weather I've 
mentioned lately in the deep tropics east of the Lesser Antilles 
struggles to get organized (it exited Africa on Aug 19).  It still has 
persistent deep convection, but it is still well separated from the 
low-level center.  It's located at about 20N 46W.
Please visit my tropical Atlantic headquarters.

25 August 2005

Katrina bearing down on FL, nearly a hurricane...

The storm has gradually intensified and slowed down, now moving west at 
just 5kts, with further slowing expected prior to landfall.  That should 
put the eyewall ashore around 10pm EDT, probably at or near Fort 
Lauderdale, FL (it would be their first direct hit since 1964).  It's 
crossing over the Florida Current, a channel in the ocean floor with a 
constant re-supply of warm water (30.5C+).  Based on experience and some 
objective models, there still exists a decent chance of rapid 
intensification in the next few hours before the eyewall hits land.  A 
competing factor seems to be some dry air on the north and west sides 
of the storm.

A buoy just east of Cape Canaveral is now reporting 9ft waves, and 
growing rapidly (their normal non-storm wave height is about 1.5ft).  
The core is still far enough from land (40 miles or so) that the strong 
winds have not reached Fort Lauderdale as of this writing... they are 
currently reporting sustained winds of 15kts, gusting to 25kts.  At 16Z 
today, TS Katrina was located at 26.2N 79.4W and tracking W at 5kts.  
It is being monitored constantly by aircraft and by ground-based radar, 
and the latest intensity is 55kts and 990mb (fell 7mb in 2 hours).  A 
Hurricane Warning is in effect for all of the southeastern FL peninsula, 
and a Tropical Storm Watch is in effect for the Keys and the 
southwestern FL peninsula.  I suspect the central FL panhandle will have 
a hurricane watch issued later today or early tomorrow for them.

Another interesting question is, what happens after tonight's landfall?  
Although there is rather large divergence among model forecasts, the NHC 
shows the storm crossing westward over the peninsula, exiting into the 
Gulf, then recurving to the north and hitting the central FL panhandle 
early Monday morning as a hurricane.  Again, there is the chance it 
could be rather intense if it has the time.
Please visit my tropical Atlantic headquarters.

23 August 2005

Jose hits Mexico, TD12 forms over the Bahamas...

As expected, TS Jose made landfall on the Mexican coast and has since 
weakened considerably inland.

Of much greater concern is TD12.  Although one can make a very strong 
case for it being the remnants of TD10, the NHC called it TD12... it was 
upgraded to a Depression this afternoon based on an aircraft recon 
flight into it.  The center is not exactly easy to find, as there 
appears to be at least a couple of them.  However, the convection is 
very intense, the SSTs are incredibly warm, and the vertical shear is 
minimal.  This will likely be upgraded to TS Katrina in the next 12-18 
hours.

At 21Z, TD12 was located at 23.2N 75.5W and tracking NW at 7kts.  The 
maximum sustained winds are 30kts and the MSLP is 1007mb.  This motion 
is expected to continue for a couple days, then turn west as a ridge 
builds to its north.  What this means is that it should turn directly 
into the southern tip of Florida as it intensifies.  Then, after 
crossing the tip of the peninsula, it should enter the Gulf and be under 
ideal conditions for rapid intensification.  If you're in FL or along 
the northern Gulf coast, be sure to check out the track forecast!  This 
is a small system, and has the ability intensify very quickly.

Further east, the large circulation I've been mentioning is still out 
there at about 18N 37W, but the convection is all displaced east of the 
low-level center.  It's seemingly very close to being upgraded to TD13 
if the convection persists.
Please visit my tropical Atlantic headquarters.

22 August 2005

TS Jose forms in Bay of Campeche...

From what I can tell, the wave that was ahead (west) of ex-TD10 crossed 
the Yucatan Peninsula last night and emerged over the Bay of Campeche 
this morning.  It very promptly organized and was upgraded to TD11.  
Over the next few hours, it continued to organize and intensify, and an 
aircraft recon flight into it found that it was indeed a tropical storm, 
and was upgraded to TS Jose this afternoon... the earliest 10th named 
storm ever in the Atlantic (by one day).  At 22Z, TS Jose was located at 
19.6N 95.4W and tracking W at 5kts.  Intensity measured by aircraft was 
45kts and 1002mb.  It should make landfall on Mexico later this evening 
as a tropical storm and then rapidly deteriorate inland.

The remnants of TD10 are still easily trackable, now near Hispaniola.  
The wave is very weak, but still has sporadic convection and nice 
curvature in visible satellite imagery.  It will continue to be 
monitored closely, because it's heading for Florida, so IF it 
regenerates, things could get interesting.

Elsewhere, a very large wave exited Africa on August 20, and is now at 
about 16N 34W.  It's a bit far north for the classic track across the 
deep tropics, so if it forms, would likely recurve somewhere in the 
central Atlantic.  It's also lacking deep convection at this time, but 
conditions should remain favorable in the foreseeable future and this 
could become TD12 in the next couple of days.  The next name on deck is 
Katrina.
Please visit my tropical Atlantic headquarters.

Atlantic Earliest "N-th" Storm Records

From Gary Padgett:
 
Back in July I looked up the earliest occurrences of Atlantic
TCs number 6 - 12 within a season.     Dennis, Emily, Franklin,
Gert, Harvey and Irene all set new records for the earliest
4th, 5th, 6th, 7th, 8th and 9th tropical storms, respectively.
 
Following is an updated table for TCs 10 - 21:
 
Number     Number of            Earliest                 2nd Earliest                        3rd Earliest 
 of TS      Occurrences
-------------------------------------------------------------------------------------------------------------------------------------------------
10th TS         many             23 Aug 1995 (Jerry)       26 Aug 1933                   28 Aug 1936
11th TS         many             28 Aug 1933                 28 Aug 1936                   28 Aug 1995 (Karen)
12th TS         many             29 Aug 1995 (Luis)        31 Aug 1933                     7 Sep 1936
13th TS           17                 8 Sep 1933                  8 Sep 1936                    13 Sep 1995 (Marilyn)
14th TS           13               10 Sep 1933                 10 Sep 1936                    27 Sep 1995 (Noel)
15th TS             7               16 Sep 1933                 19 Sep 1936                    30 Sep 1995 (Opal)
16th TS             6               27 Sep 1933                   5 Oct 1995 (Pablo)           9 Oct 1936
17th TS             4               28 Sep 1933                   9 Oct 1995 (Roxanne)     21 Nov 1969 (Martha)
18th TS             3                1 Oct 1933                   21 Oct 1995 (Sebastien)    4 Dec 1887
19th TS             3               25 Oct 1933                  27 Oct 1995 (Tanya)          7 Dec 1887
20th TS             1               26 Oct 1933
21st TS             1               15 Nov 1933
 
All the above is based on the current Best Track file, which has been re-analyzed for the
years 1851 - 1910.   Information for 1911 onward will be subject to revision, and this
could affect stats for some of the busier seasons, especially 1916, 1933 and 1936.
 
 
Please visit my tropical Atlantic headquarters.