28 September 2004

Jeanne drenching the eastern seaboard, Lisa still a TS...

So far 9 deaths have been blamed on Jeanne in the US, and about 1500 in
Haiti and Dominican Republic (with 900+ still missing).  Although not
producing tornadoes as prolifically as Ivan did, Jeanne has produced a
few, but the main story is RAIN... 1-2 feet at places.  Heavy rain over
the same areas that saw rain from Charley, Frances, and Ivan.

Of the big landfalls this year, Jeanne has been the least deadly in the
US, but the most deadly overall.  Charley, Frances, and Ivan were
responsible for 82 US fatalities combined.  Sadly, some long-dead are
coming back to the surface too; the rain-soaked earth in the southeast
is letting buried coffins in cemetaries come to the surface, creating a
rather unpleasant clean-up job.  The worst of the weather associated
with Jeanne is now hitting MD, PA, NJ, and NY, where Tornado and Flood
Watches/Warnings cover those states.

Despite forecasters' urge to strengthen the storm, Lisa has remained a
strongly-sheared Tropical Storm, no threat to land.  The convection has
been displaced from the low-level center for days now, so until that
corrects itself, it will not be able to intensity much, if at all.  At
15Z, TS Lisa was located at 25.0N 47.1W and moving N at 10kts. 
Satellite-estimated intensity is 45kts and 1000mb.

Elsewhere, there is a tropical wave at about 30W that is not very well
organized at the moment, but should be watched for development over the
next few days.  A couple of reliable computer models favor it, while the
rest do not.

As of this afternoon, the season's NTC (Net Tropical Cyclone activity)
is 218%.  In other words, this measure shows that more than twice the
activity of an entire average season has already occured.  This puts
2004 in 4th place since 1900, only behind 1995 (222%), 1926 (229%), and
1950 (230%).  Two more months until the official end of hurricane
season.  A remarkable facet of this season is that out of the 7
hurricanes we've had, 6 of them have made it to CAT3 or higher.  On top
of that, they have generally maintained that intensity for 1.8x longer
than the typical major hurricane.

Please visit my tropical Atlantic headquarters.

26 September 2004

Jeanne slams Florida, Lisa still no threat to land...

At about midnight local time, Jeanne made landfall near Port St. Lucie, FL as a 100kt CAT3 hurricane, very close to where CAT2 Hurricane Frances made landfall three weeks prior.  I attached a radar image from landfall as seen from the Melbourne radar.

Jeanne has since moved inland across the peninsula and will move over the panhandle later tonight.  It's too early to get an idea of the damage, but from the preliminary reports, it sounds very severe.  It is now a weakening 55kt Tropical Storm and the central Low pressure will continue to fill as it tracks northward over the southeast US states.

Lisa remains poorly organized, and is currently a 45kt TS.  With weaker vertical shear in the forecast however, she is expected to become a minimal hurricane in a few days, but still out in the open Atlantic, far from any land.  At 21Z, TS Lisa was located at 19.7N 46.1W.

For the first time in almost two months, there is nothing on the immediate horizon in terms of formation, so once Jeanne is over with in a day or two, Lisa will still be churning up the central Atlantic, and maybe all will be quiet for a brief time during this historical season.

Please visit my tropical Atlantic headquarters.

25 September 2004

Jeanne just hours from landfall, Lisa strengthens slightly...

As feared, Jeanne has intensified to a CAT3 hurricane, the 6th of the season, and is still seemingly growing stronger.  The center of the eye  is between the Bahamas and the FL coast now, and should make landfall near Vero Beach around midnight local time.  This is nearly identical to the track of Frances, who made landfall there 3 weeks ago.  That stretch of land is certainly living up to its claim of the most frequently-hit spot on the entire US coastline this year.  However, I think this is the first year to have 4 hurricane landfalls in FL during the same year.

At 21Z, Hurricane Jeanne was located at 27.1N 78.8W and tracking W at 12kts.  Maximum sustained winds are 100kts and the MSLP is 950mb. Although currently a CAT3, it could easily reach CAT4 status by landfall.  Hurricane Warnings/Watches cover basically all of the FL coastline, and into the southern GA coast.

At 09Z today, Lisa was upgraded to a Tropical Storm again, and now has an intensity of 35kts and 1002mb.  The vertical wind shear is quite high, and the forecast track is similar to Karl's... heading north into the open Atlantic, no threat to land at all.

Please visit my tropical Atlantic headquarters.

24 September 2004

Ivan makes another landfall, Jeanne heading for Florida, Karl becomes extratropical, and Lisa weakens...

At about 02Z this morning, Ivan made another US landfall, this time as a
Tropical Storm just south of Lake Charles, LA.  It has since moved
inland over TX and has produced 3-4" of rain, but quite insignificant
compared to its first US landfall.  As far as I know, the death toll
associated with Ivan is only around 120 people in the Caribbean and US

Jeanne, on the other hand, has been terribly deadly, with about 1200
fatalities reported so far, and another 1300 still missing in Hispaniola
alone (mass graves have been dug for the human and animal corpses, so
it's BAD).  She has now completed a small loop and is heading west
directly toward the Florida peninsula.  Now that forward motion has
resumed and shear has lessened, it should intensify steadily.

As of 21Z, Jeanne was located at 26.4N 73.5W and tracking W at 10kts. 
Maximum sustained winds are 85kts and MSLP is 965mb.  As shear decreases
and SST increases, it is forecast to strengthen to a CAT3 storm by
landfall... expected Sunday morning between Cape Canaveral and West Palm

A Tropical Storm Warning is in effect for the central Bahamas.  Tropical
Storm Watch for most of the western FL peninsula.  Hurricane Watch for
the extreme northern FL and GA coast.  And Hurricane Warnings for the
western Bahamas and almost all of the eastern FL peninsula.  Nearly 1/2
million evacuations have already been ordered on the FL peninsula...

The final advisory was written on Karl this afternoon, nearly at 50N! 
He has become absorbed by the mid-latitude trough and is now a potent
extratropical storm destined to give Iceland a rough ride in a couple

Lisa has been a Tropical Depression since the update I sent out
yesterday, and that's entirely due to strong northerly shear.  There has
been active deep convection, but none of it is over the low-level
circulation!  The interaction with the strong tropical wave has
basically ended, with Lisa the victorious vortex.  Still way out at
about 15N 45W, she's forecast to head quickly to the north as a strong
TS, folling almost in Karl's footsteps.

Please visit my tropical Atlantic headquarters.

23 September 2004

Ivan regenerates, Jeanne heading for US coast, Karl and Lisa still over open ocean...

At 23Z last night, the remnants of the once-great Ivan regenerated in
the north central Gulf of Mexico.  After making landfall in Alabama, the
low-level center passed over GA, NC, VA, MD, then offshore and moved
south, crossing over Florida on Monday, then finally to where it is
now.  Yes this is unusual, but the whole season has been, so it's no
surprise.  TS Ivan is now just a few miles off the southwest LA coast
and should make landfall (again) shortly, then head inland over
southeast TX.  Latest intensity was 40kts and 1003mb, and tracking NW at

Jeanne has just about completed her little loop northeast of the Bahamas
and is set to head toward the US coast.  Satellite presentation has been
improving throughout the day, and it's also been upgraded to a CAT2
storm.  Further intensification is likely before making landfall on the
FL peninsula (most likely) on Sunday morning.  At 21Z, Hurricane Jeanne
was located at 25.9N 70.3W and heading WNW at 7kts.  Maximum sustained
winds are up to 90kts and the MSLP is 966mb.

Karl is rapidly being absorbed by a mid-latitude trough, but still a
CAT2 hurricane out near 36N 42W.  This hurricane which has been in the
picture for a full week now is close to becoming extratropical.

Lisa is still a TS, and having trouble organizing as it interacts with
the strong tropical wave immediately east of it.  The forecast however,
is for gradual strengthening and a turn to the north just like Karl.

Please visit my tropical Atlantic headquarters.

22 September 2004

Jeanne, Karl, and Lisa still churning up the Atlantic...

Jeanne is now a CAT2 hurricane, and is in the process of making a small
loop, eventually heading back toward the west, and forecast to hit the
southeast US in a few days as a hurricane.  As of 21Z today, Hurricane
Jeanne was located about 500 miles east of the Bahamas with an intensity
of 85kts and 967mb.

Karl has been a CAT3/4 hurricane for a while, until this morning when it
was downgraded to a CAT2.  Further weakening is expected as it merges
with a strong mid-latitude system and makes the extratropical
trasition.  Latest intensity is 90kts and 970mb.

Lisa, the one that formed immediately east of Karl, has not moved too
far, and is having great difficulty intensifying; however, only
partially because of Karl's outflow.  The wave just a few degrees to her
east has become much better organized and is in fact looking healthier
than Lisa.  The ensuing binary interaction will be interesting to watch,
and see which vortex is victorious.  Lisa is still a Tropical Storm with
45kt maximum sustained winds and 997mb MSLP.

A fragment of Ivan dropped down along the east coast, crossed Florida,
and is now in the central Gulf of Mexico.  It has persistent deep
convection, but is strongly sheared right now.  However, if the shear
decreases, Ivan could make a comeback, but would almost certainly get a
new name.  IF it becomes something of note, it could affect LA or TX in
the next few days.

Please visit my tropical Atlantic headquarters.

20 September 2004

Jeanne a hurricane again, Karl still a major hurricane, TD13 upgraded...

At 21Z today, TS Jeanne was upgraded to a hurricane again, based on
aircraft recon (recall the last time she was a hurricane was 4.5 days
ago as she made landfall on Hispaniola, and has since killed over 250
people on that island).  Current location is 27.4N 71.2W and heading NE
at 6kts.  The storm is under weak steering flow, and that makes the
forecast track very challenging, so for the most part, the long-range
forecast is for it to basically stall, but maintain hurricane
intensity.  Maximum sustained winds are now 75kts and MSLP is 983mb.

Karl is still a major hurricane, and not a threat to land.  Presently at
18.6N 47.1W and tracking NW at 10kts, a sharp recurve to the north is
expected soon.  Latest satellite-estimated intensity is 105kts and

At 12Z this morning, TD13 was upgraded to TS Lisa, the 12th named storm
of the season.  As of 21Z, Lisa was at 13.8N 36.8W and moving W at
10kts.  Still VERY close behind Karl, the intensity is a remarkable
55kts and 994mb.  This is an interesting case of tropical cyclogenesis
in the immediate neighborhood of a major hurricane.  Unlike her big
brother Karl, Lisa is expected to continue heading west *slowly* maybe
reaching the Lesser Antilles in 8-10 days.

Elsewhere, there's a borad impressive tropical wave just behind Lisa at
about 26W that will be watched for further organization.

So, although there are 2 hurricanes and a tropical storm out there, none
of them will be affecting land in the near future, if at all.

Please visit my tropical Atlantic headquarters.

19 September 2004

Jeanne strengthens, Karl a major hurricane, TD13 forms...

Since exiting the coast of Hispaniola as a small disorganized Depression, Jeanne is now a much bigger, more organized Tropical Storm.  However, despite the improvement, there is still minimal convection near the inner core, so intensification will hold off until that occurs.  As of 21Z today, TS Jeanne was located at 24.5N 72.3W and heading. Winds are 45kts and MSLP is 996mb.  Gradual strengthening is forecast over the next 3 days, followed by weakening due to increasing vertical wind shear.  The forecast track keeps Jeanne well away from the US.

Karl was upgraded to the 5th major hurricane of the season at 03Z today, and is now a CAT4 storm.  Environmental conditions are basically ideal, and maximum sustained winds are estimated at 115kts, and the MSLP at 944mb.  It is forecast to reach 125kts, same intensity as Charlie and Frances at their peak intensities.  The storm is located at 17.0N 44.0W and tracking WNW at 9kts.  This large hurricane should begin heading due north through a weakness in the subtropical ridge within a day or so.

At 21Z today, TD13 formed immediately east of Karl (about 850 miles). Latest intensity is 30kts and 1004mb.  Due to the proximity to Karl, the system will suffer from strong vertical shear, and the steering flow is virually identical, so the forecast track is very similar.  If and when this Depression gets named, it will be TS Lisa.

Please visit my tropical Atlantic headquarters.

17 September 2004

Ivan still decaying, Jeanne weakens, Karl forms...

The large circulation of Ivan's remnants are still producing heavy rain
and tornadoes over much of the eastern US.  The total death toll is at
about 75 people in the Caribbean and US.  Also of great interest is that
Ivan has set the all-time record for amount of time spent as a major
hurricane: 10 days.  This will certainly be one of the most memorable
storms in history, joining the ranks of Camille '69, Frederic '79, Allen
'80, Hugo '89, Andrew '92, and Opal '95.

Jeanne had stalled over Hispaniola, but is now starting to drift WNW
over the open ocean.  This basically shredded the integrity of the
former hurricane, and is now a Tropical Depression, with all convection
to the east of the low-level center.  So far 6 deaths have resulted from
the flooding in Puerto Rico and Dominican Republic.  As of 21Z, TD
Jeanne was at 20.2N 71.8W with maximum sustained winds of 1002mb.  The
forecast is for slow weakening, but perhaps not even reaching hurricane
strength again.  Still, residents from FL to NC should watch its
progress closely.

At 03Z today, TD12 was upgraded to TS Karl, and it's still on an
intensifying trend.  Latest intensity is 55kts and 994mb.  Convection
and banding have improved, and Karl is expected to become the 7th
hurricane of the season within 12-18 hours (then perhaps the 5th major
hurricane within 3 days).  The good news is that it will almost
certainly recurve into the open ocean well before reaching even the
Lesser Antilles, let alone the US.

As of 21Z today, the season is 66% more active than an entire full
hurricane season, and there are still 10 weeks to go.

Please visit my tropical Atlantic headquarters.

2004's place in history

From Phil Klotzbach:

First of all, after double-checking the numbers,  Ivan has the most intense hurricane days of a single storm on record with 10.0, extending back to 1900.  The second place storm was the Miami 1926 storm (Storm 4 of that year) with 9.25 IHD, and in third place was Donna from 1960 with 9 IHD.
Here are my calculations for the months of August and September (up to 15Z on September 17) and for the season as a whole.  I'd be interested to see how they compare with the numbers that you guys have calculated.  I have put in parentheses its all-time rank if ranks in the top 10 all-time since 1950.


NS: 8 (Rank: 1)
H: 4 (Rank: T-2)
IH: 3 (Rank: 1)
NSD: 32 (Rank: 3)
HD: 14.75 (Rank: 4)
IHD: 5.25 (Rank: 5)
NTC: 85.3 (Rank: 1)


NS: 3
H: 2
IH: 1
NSD: 24.25
HD: 16.5
IHD: 13 (Rank: 3)
NTC: 80.9 (Rank: 9)


NS: 11
H: 6
IH: 4 (Rank: T-8)
NSD: 56.25
HD: 31.25
IHD: 18.25 (Rank: 2)
NTC: 166.2 (Rank: 9)

This season has been quite remarkable so far.  We already have the 2nd most intense hurricane days for a season on record... the only year with more was 1961 with 21.5 IHD.  I'll try to run some more calculations in the next few days.

Please visit my tropical Atlantic headquarters.

16 September 2004

Ivan makes landfall, Jeanne makes landfall, TD12 forms...

At about 07Z today, "Ivan the Terrible" made landfall at Gulf Shores,
AL, a fairly small town on the east side of Mobile Bay, and just a few
miles west of the FL panhandle.  Locations from Gulfport, MS to Fort
Walton Beach all suffered substantial damage, while locations further
inland were enduring deadly tornadoes spawned in Ivan's rainbands. 
Intensity at landfall was about 100kts, but post-landfall analysis of
observations and damage will pinpoint that better.  So far 36 tornadoes
have been reported in FL, GA, and SC since landfall, causing at LEAST 12
fatalities and 15 injuries.

Ivan has weakened to a Tropical Storm now, and is near Birmingham, AL. 
Intensity is 50kts and 980mb, with a heading of NNE at 12kts.  It will
continue to move NE over TN, then perhaps loop back E then SE toward SC
and interact with Jeanne in about 6 days.  Stranger things have
happened.  I'll close today's discussion of Ivan with some relevant
remarks made today:
"I've been through a lot of hurricanes, but this is the most ungodly
thing I've ever seen"  -- Robert Randle, Gulf Breeze deputy police

"This couldn't be much worse."  -- John Fogg, mayor of Pensacola

"It would be easier to say what's NOT damaged,"  -- Ted Roy, Escambia
County sheriff's department.

I found this quote on CNN's website which I thought was very fitting:
"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

Now on to Jeanne.  Jeanne was upgraded to the 6th hurricane of the
season at 12Z today, then made landfall on the Dominican Republic and
went on to actually form an open eye while over the mountainous island. 
At 21Z, it was downdraged to a Tropical Storm again, but that should be
temporary.  It is now expected to head back over water and toward the
Bahamas.  The SE US coast should be watching this one very closely, as
it could be another hurricane landfall in about 5 days.  Current
intensity is 60kts and 990mb.

Elsewhere, that large tropical wave I've mentioned that past couple of
days is now TD12, based on satellite presentation.  It's out at 11.4N
32.8W and heading W at 14kts.  Maximum sustained winds are 30kts and
MSLP is 1007mb, but it's forecast to quickly become Tropical Storm Karl,
then a hurricane in about 2 days.  The latest thinking is that it will
recurve into the central open Atlantic, but I have to wonder how likely
that is given the current location south of 12N.  Something to watch... 

Please visit my tropical Atlantic headquarters.

15 September 2004

Gulf Coast prepares for a hard hit, Puerto Rico takes a direct hit...

Ivan is now just 120 miles from the coast, or about 8.5 hours (21Z fix
had it at 28.4N 88.3W).   Heavy rainbands have moved onshore, and the
eyewall will move onshore in perhaps 6 hours.  The exact location of
landfall will not matter since this is such a large strong storm. 
However, Mobile is forecast to take the center of the eye during the
early morning hours on Thursday.  Buoys in the gulf ahead of Ivan have
reported waves up to 50 feet high.

Recent aircraft recon suggests that Ivan is intensifying.  The pressure
has fallen noticeably, and the objective satellite techniques all show
an intensifying trend.  But as of now, the maximum sustained winds are
held constant at 115kts.  MSLP is 933mb.  Ivan should make landfall as a
CAT4 hurricane, and unfortunately, that means the damage will be
widespread and extreme.  Storm surge flooding, rainfall flooding,
tornadoes, and hurricane-related winds will result in a very scary night
tonight as he makes landfall.

Jeanne made landfall on Puerto Rico at about 18Z as a strengthening
Tropical Storm.  Current intensity is 60kts and 991mb.  It is expected
to exit the island, then head WNW past Hispaniola then into the
Bahamas.  It's presently at 18.4N 66.5W and tracking WNW at 8kts.  This
motion is expected to continue.  Again, residents along the southeast US
coast should keep a close eye on Jeanne in the coming week.

The strong tropical wave I mentioned yesterday has become better
organized, and is presently at about 10N 28W (south of the Cape
Verdes).  It's moving WNW at about 16kts and has a 1010mb Low associated
with it.  Given the warm SSTs and low shear, this should become TD12
within 18-24 hours.  The next name on the list is Karl.  

Please visit my tropical Atlantic headquarters.

Ivan nearing Gulf Coast, Jeanne nearing Puerto Rico...

Ivan is still a mighty CAT4 hurricane at is takes aim at the northern Gulf Coast.  Evacuations are being rushed, especially in New Orleans where they are particularly vulnerable.  The city exists 5 feet below sea level, protected by dikes.  A direct hit or even a near-miss would result in the costliest disaster in US history as the entire city fills with perhaps 15+ feet of water.  The 09Z forecast track takes the eye into Mobile, AL, which is still quite bad, for Mobile and places far east and west of it due to the storm's large eyewall.  Latest position is 165 miles away from landfall, or about 13 hours.

TS Jeanne is currently very near hurricane-strength at 60kts and 991mb.  The center of the circulation is just a few miles off the southeast coast of Puerto Rico, with evidence of an eyewall forming.  She will almost certainly be upgraded to the 6th hurricane of the season within the next 12 hours.  The forecast is for slight strengthening beyond Puerto Rico, but still facing the outflow/shear from Ivan.  In a couple of days, conditions should improve as it heads over the Bahamas and intensifies, heading toward the US coast... at this point, anywhere from FL to NC should be watchful.

Please visit my tropical Atlantic headquarters.

14 September 2004

Ivan still a CAT4, TD11 becomes TS Jeanne...

At 06Z today, Ivan was downgraded to a still-powerful CAT4 hurricane as
it entered the Gulf of Mexico.  It now has a very large eye and is
heading for a patch of high oceanic heat content which could allow it to
intensify yet again.

The 21Z position was 24.2N 86.6W and motion was NNW at 8kts.  Maximum
sustained winds are 120kts and MSLP is 929mb.  The forecast is slowly
becoming more certain as it gets closer, and the region between New
Orleans and western FL panhandle look like the highest risk areas now. 
The official NHC forecast takes it into Mobile, AL as a CAT3 storm in
the early morning hours on Thursday.  Hurricane Warnings cover a stretch
of land from Grande Isle, LA to Apalachicola, FL, and evacuations have
already begun in many places contained in that warning.  Personal
intuition tells me that New Orleans should be especially cautious.

At 15Z today, TD11 was upgraded to TS Jeanne, the 10th named storm of
the season.  It crossed directly over Guadeloupe as a strengthening TD,
so conditions wouldn't have been TOO bad there.

As of 21Z, she's at 16.8N 63.9W and tracking WNW at 9kts.  Intensity is
50kts and 998mb.  The forecast is for gradual intensification, passing
directly over Puerto Rico as a hurricane, then skipping north of
Dominican Republic and into the Bahamas in 5 days.  Residents from FL to
NC should be watching Jeanne closely.

Elsewhere, there is an impressive tropical wave in the deep tropics near
25W.  This circulation will be monitored for future development.

Please visit my tropical Atlantic headquarters.

13 September 2004

Ivan passing by Cuba as CAT5 storm, TD11 forms...

At 03Z today, Ivan was upgraded to a CAT5 hurricane for the third time. 
The latest aircraft recon found maximum sustained winds of 140kts and
the MSLP is 912mb (910mb was found since the advisory).

It's presently just a few miles off the western tip of Cuba and heading
northwest through the Yucatan Channel.  A Gulf Coast landfall is
inevitable; the obvious question is WHERE.  The primary threat region
appears to be between New Orleans and Tampa, with the FL panhandle in
the highest risk zone.  Timing would place it near the US coast
Wednesday night.  Luckily, the Keys residents who evacuated earlier are
being allowed back in due to the unexpected westerly track over the
weekend (always better returning home after a miss than a hit!).  

This major storm has killed at least 62 people so far: 17 on Jamaica, 37
in Grenada, 4 in Venezuela, and 4 in Dominican Republic.  Ivan has now
spent more time as a major hurricane than Frances, and is possibly on
its way to breaking the all-time record.

At 21Z, a disturbance just east of the Lesser Antilles was upgraded to
TD11.  It exited the African coast on Sept 7 and is now nearing
Guadeloupe in the southern Leeward Island chain.  As of 21Z, TD11 was
located at 16.0N 60.4W and tracking WNW at 10kts.  It's expected to
track over or near the British Virgin Islands, US Virgin Islands, Puerto
Rico, perhaps parts of Hispaniola, then the Bahamas.

Current intensity is 30kts and 1010mb.  The immense outflow from Ivan
will likely keep pretty high shear over TD11 for the next couple days,
but further intensification is forecast once the shear and landmasses
are in the past.  If named, this will be TS Jeanne.

Please visit my tropical Atlantic headquarters.

11 September 2004

Ivan now past Jamaica, heading for Cayman Islands...

Around midnight local time last night, very powerful Ivan approached the Jamaican coast, and miraculously turned to the west, keeping the eyewall JUST offshore.  After passing the island, it resumed its WNW course.  So although I'm sure the destruction due to flooding and some high winds on Jamaica will be hefty (7 deaths already reported there), they really got incredibly lucky.  On the flip side, this also allowed Ivan to continuously intensify, since the inner core remained over extremely warm water.  My preliminary count has the death toll at already about 40 people, from Grenada, Venezuela, Dominican Republic, Barbados, and Jamaica.

At 21Z today, it was upgraded its strongest intensity yet based on aircraft recon.  It's at 145kts and 914mb... one of the stronger hurricanes to ever exist in the Atlantic, and still strengthening perhaps.  It is forecast to hit western Cuba as a CAT5 early Monday morning.  First though, it looks like it will pass directly over Grand Cayman early Sunday morning, also as a CAT5.  Present location is about 140 miles ESE of Grand Cayman, and heading WNW at 8kts.

Although the current forecast track takes it into the central FL panhandle early Wednesday, I personally believe it's simply too early to pinpoint a location... there are some uncertain variables that make this too questionable so far out.  Anyone on the panhandle, western peninsula, and the Keys should be preparing for this.  Also of great importance is the trough that's steering it northward will also weaken it a bit before it hits the US due to increasing vertical wind shear.

Please visit my tropical Atlantic headquarters.

10 September 2004

Ivan aircraft recon...

Although Hurricane Ivan looked slightly ragged last night and much of
today, it appears to now be taking full advantage of the increasing
oceanic heat content and could be at the onset of another rapid
intensification phase.  The frequency of in-situ measurements made by
aircraft is wonderful.  Here I'll include a table of some parameters
throughout the day when aircraft were in the storm:

TIME (UTC)   MSLP (mb)   EYE DIAM (nm)   ODT T#
1023         934         20              5.3
1105         934         20              5.3
1738         940         16              5.7
1913         937         16              5.8
2037         933         15              6.0
2215                                     6.2

So, you'll notice the eye has been contracting throughout the day which
will also lead to intensifcation.  The Objective Dvorak Technique
T-numbers are using just infrared satellite imagery, and are a function
of cold cloud tops over the eyewall and a warm eye... the higher the
number, the stronger the storm, objectively.

Please visit my tropical Atlantic headquarters.

Ivan very near Jamaica...

During the night and early morning hours, Ivan went through an eyewall
replacement cycle, and was hit by light northwesterly wind shear, and
weakened to 120kts as a result, but still a CAT4 hurricane.  The latest
satellite imagery shows gradual strengthening again, with the coldest
cloud tops wrapping around a clearing eye.

As of 21Z, Hurricane Ivan was located at 17.0N 76.2W and tracking WNW at
11kts.  Aircraft-measured intensity is 120kts and 937mb.  The storm is
just now entering enhanced SSTs and oceanic heat content as it nears
Jamaica and then again between Jamaica and Cuba.  The very dangerous
storm is just 80 miles away from Jamaica, and is expected to hit it
head-on tonight (around 1-2am local time) as a CAT4 storm... even
stronger than Gilbert '88 which was totally devastating.  Major
hurricane-force winds could ravage the island for up to 8 hours.

The death toll has already reached 25, and it hasn't even hit Jamaica,
Cuba, or the US yet.  But hopefully enough precautions and evacuations
have taken place that people will be safe.  The Florida Keys are
presently being evacuated.

The forecast is certainly of great interest to a LOT of people.  It
looks more and more apparent that Florida is indeed the target of yet
another tropical assault.  Jamaica will be hit late tonight, then
western-central Cuba on Sunday evening, then it should be very close to
the FL Keys midday Monday.  It is too early to give an exact landfall
location in mainland FL, aside from saying the panhandle and western
peninsula.  Intensity at US landfall will depend on what effects Cuba
has on it, so we'll have to wait until early Monday perhaps to see that.

Please visit my tropical Atlantic headquarters.

09 September 2004

Ivan taking aim on Jamaica...

Mighty Hurricane Ivan maintained CAT5 status until 21Z when it was
downgraded slightly to a strong CAT4.  At this very high strength,
intensity fluctuations are perfectly normal as it responds to minor
changes in oceanic heat content and as it undergoes eyewall replacement
cycles.  It now has maximum sustained winds of 130kts and a MSLP of
921mb.  It's 350 miles ESE of Jamaica and is headed WNW at 13kts;
landfall is expected on Jamaica Friday afternoon/evening.  If it does
indeed hit them head-on at CAT4 intensity, it would be devastating. 
Some of you may recall Hurricane Gilbert '88 who hit the island as a
CAT3 and was incredibly destructive.

The forecast calls for maintaining CAT4/5 intensity as it heads over
Jamaica on Friday afternoon, western Cuba on Sunday evening, then
perhaps weaken slightly as it heads for Florida Monday evening or
Tuesday afternoon, depending on how far north it makes it before hitting
land.  Hurricane warnings are in effect for Jamaica and the Cayman
Islands, and Hurricane watches are up for virtually all of Cuba.  No
watches or warnings yet for the US.

In other news, TD10 formed from a tiny weak circulation near the Azores
Islands in the far northeast Atlantic.  It lasted for 12 hours (09-21Z
today) before NHC ceased writing advisories on it.  It was highly
sheared and no longer convectively active.

Please visit my tropical Atlantic headquarters.

Ivan rapidly intensifies...

Ivan has undergone rapid intensification during the afternoon and night on Wednesday.  At 06Z on Thursday, the already-terrible Ivan was upgraded to a Category 5 hurricane, the first of the season.  The last CAT5 was Isabel '03, then before that was Mitch '98.

Ending at 06Z, the pressure fell 13mb in 3 hours and 24mb in 12 hours. Winds have reached 140kts (160mph) and the central pressure is now 925mb.  This extreme intensity is difficult to maintain for very long, so it could easily drop back down to a CAT4, but still very dangerous.

It is presently located north of the tiny islands of Aruba, Bonaire, and Curacao off the Venezuelan coast.  The official forecast takes it directly over Jamaica on Friday afternoon, western Cuba on Sunday afternoon, and the southwest Florida peninsula on Monday evening... all as a CAT4.  Keep in mind the later forecast times become increasingly uncertain.

Please visit my tropical Atlantic headquarters.

07 September 2004

Frances decays inland, Ivan thrashes the Windwards...

At 03Z today, NHC issued the final advisory on Frances, now a large
weakening swirl centered over Atlanta.  However, she will not be
forgotten.  Over 3 million people are still without power, and 16 people
have died in the Bahamas, Florida, and Georgia.  The storm was a
hurricane for 10 full days, and a major hurricane for 7.25 of those

Ivan is gradually regaining intensity, and became a CAT3 again at 09Z
today.  As of 21Z, it was at 12.0N 62.0W and moving quickly to the west
at 16kts.  Aircraft-measured intensity is 105kts and 956mb.  Given
nearly ideal conditions, Ivan is forecast to intensify further, reaching
CAT4 within 6-12 hours.

The northern eyewall and eye passed directly over the island of Grenada
at 22Z today.  Grenada is the southernmost island in the Windward Island
chain with a population of nearly 100,000.  Since that only occurred
only one hour ago as of this writing, no damage reports are in, but they
will be significant.  I don't usually do this, but I included an
attachment showing a visible satellite image, taken near local sunset,
just as Ivan was passing over Grenada... looks peaceful from space, but
remember under those pretty clouds are sustained winds of 120mph.
The forecast track is very easy in the short term, but extremely
challenging in the long term.  Over the next couple of days, Ivan will
continue heading W to WNW outside the periphery of the subtropical
ridge.  Beyond then, it's too hard to say if the ridge will decay at
all, or to what degree.  This affects the track immensely: a weaker
ridge means it will nudge northward, toward the Greater Antilles and
perhaps Florida; a stronger ridge means it will keep heading WNW toward
the Yucatan Peninsula.  It's simply too early to tell.  

The tropical wave I mentioned yesterday is still heading west, and
presently located at about 16N 37W.  It shows signs of development, and
should become TD10 very soon.  If it gets named, it would be Jeanne. 
Given its position so far north at 37W, it would most likely recurve
before reaching the Lesser Antilles, but will be monitored closely.

Please visit my tropical Atlantic headquarters.

06 September 2004

Frances makes landfall (again), and powerful Ivan heading for Lesser Antilles...

Frances exited the Florida peninsula near Tampa as a Tropical Storm, and
tracked across the northeastern Gulf of Mexico, never regaining
hurricane strength.  It made landfall again near St. Marks in the
Florida panhandle at 2pm EDT as a strong Tropical Storm.  But the heavy
rain spans from near Tampa to central GA.  There are already 11 tornado
reports today in FL, GA, and SC associated with Frances' rainbands. 
Tornado, Flood, Flash Flood, and Tropical Storm Watches/Warnings cover
much of FL, GA, AL, and SC.  At 21Z, the center of TS Frances was
inland, about 75 miles northeast of Apalachicola, and moving NNW at
7kts.  Maximum sustained winds have dropped to 40kts and the MSLP is up
to 982mb.

After Ivan's extremely rapid intensification on Sunday (30mb in 6
hours), the inner core basically collapsed and the storm weakened as a
result.  This was part of an eyewall replacement cycle, which as of this
writing, is still occuring.  Once complete, the central pressure should
drop fairly quickly again.  It is still 300 miles east of the Windward
Islands, and is heading directly for Barbados.  As of 21Z, Hurricane
Ivan is located at 11.6N 55.3W and tracking WNW at 19kts.  Intensity
measured by aircraft was 90kts and 968mb.  Further strengthening is very
likely, and it should be upgraded to a CAT3 storm again within 6-12
hours.  The Lesser Antilles can expect the worst weather midday Tuesday.

The forecast track takes Ivan over Hispaniola (a mountainous island
between Cuba and Puerto Rico comprised of Haiti and the Dominican
Republic) midday Thursday, then PERHAPS knocking on Florida's door early
this weekend.  The southeastern FL peninsula is climatologically the
most frequently hit slice of land along the entire US coastline, and
this year is certainly validating and enhancing that statistic.

Elsewhere, a healthy tropical wave is located in the far eastern
Atlantic, at about 12N 32W.  It exited Africa last Friday (4 days behind
Ivan), and is moving W at 12kts. Conditions appear favorable for
development over the next day or two; the next number/name on deck is

As of the 21Z advisories today, this season's activity is already 19%
higher than an entire average season, and we haven't yet reached the
climatological peak!

I'd like to thank Jonathan Vigh for sending the updates in my absence. 
The ten days I was gone were host to a lot of activity (Frances, Gaston,
Hermine, Ivan), so it was no small chore.  I hope you all enjoyed his
expert analysis and commentary!

Please visit my tropical Atlantic headquarters.

Frances exits stage left, another storm that may be known as 'Ivan the Terrible'...

From Jonathan Vigh: 
Hurricane Frances was downgraded to Tropical Storm Frances at 5 pm EDT. What
is remarkable about this fact is that she made it nearly to the other side
of Florida before being downgraded. Lumbering along at 5-7 mph, her large
circulation has been very slow to weaken. Frances has now affected nearly
the entire Florida Peninsula, bringing at tropical storm force gusts all the
way from the Lower Keys up to Jacksonville. Hurricane-force gusts have been
felt along Florida's east coast from Palm Beach county all the way up to
Saint Augustine. There have not been very many reports of peak winds yet,
but there have been anecdotal reports (or estimates) by the media and others
of 100+ mph winds right along the coast. Port Canaveral reported a 124 mph
gust, but it is not known at what height this measurement was taken. Winds
almost always increase rapidly with height just above the ground, so if this
was measured on a tall tower it would not be representative of the actual
winds (the standard height to take wind measurements is 10 meters). Inland,
Orlando's main airport reported gusts as high as 69 mph (in contrast, they
had gusts to at least 105 mph in Charley), and wind gusts of 95 mph were
reported around and on Lake Okechobee. 

Most of the damage so far seems consistent with a cat 1/2 hurricane. It is
likely that the most severe damage occurred on barrier islands which have
not been surveyed yet. Needless to say, Frances hit Florida hard. Unlike
Charley, where damage was extreme, but mostly confined to a 10-mile wide
swath, Frances left spotty damage across the entire state, but a general
swath of moderate damage about 100 miles across, mostly along the coast (not
very many people live inland in the path taken by the eye after landfall).
Beach erosion has been considerable. Frances has also been much less deadly
than Charley (so far -- however, many storm deaths happen afterwards due to
accidents, electrocutions, carbon monoxide poisoning, and the like). 2 were
reported killed in the Bahamas and 2 or 3 deaths are blamed on the storm in
Florida so far. Power is out to over 2 million households and businesses.
The total damage will likely be in the billions, but it is unclear whether
it will be more or less than Charley. 

But wait, the story is not done -- no, not even yet has Frances relinquished
her desire to cause grief to the state of Florida. She is just now emerging
out into the Gulf of Mexico north of Tampa and will have 12-18 hours over
open water before making a second landfall, possibly near Apalachicola. She
is forecast to restrengthen to a minimal hurricane by this time, so more
trouble is ahead. Since she is so broad, the actual point of landfall
doesn't matter very much and winds and more heavy rains will spread far
inland over Georgia and Alabama afterwards. The bend of Florida is very
susceptible to storm surge flooding, so this will be a factor as well.
Hurricane warnings are in effect from south of Tampa all the way to Destin.
Tropical Storm Warnings are in effect for nearly the rest of Florida except
the southeast coast.   

At 03Z, Frances was at 28.3N  82.7W, moving west-northwest at 7 kt with
sustained winds of 55 kt and a central pressure of 976 mb.

If anyone is getting hurricane fatigue, they may want to skip the next
section. Unfortunately, Africa has given birth to a monster. Just a few days
ago, cute little Ivan rolled off the coast with an interesting umbilical
cord stretching back to the motherland. Now, just a few days later, Ivan is
poised to become one of the strongest storms ever seen in the Atlantic.
Here's a brief recap of the amazing developments of the past day:

Sun 03Z 991 mb 60 kt
Sun 09Z 987 mb 65 kt Ivan becomes 5th Atlantic hurricane of the year
Sun 15Z 980 mb 75 kt Ivan rapidly strengthening
Sun 17Z 960 mb 100 kt Ivan becomes the 4th major hurricane of the season
Sun 21Z 950 mb 110 kt Ivan is now perhaps the strongest hurricane on record at such a low latitude in the Atlantic basin (preliminary)
Sun 03Z 948 mb 115 kt Ivan now a cat. 4 hurricane

It should be noted that all of these intensity measurements are based
completely on satellite estimates. A plane is scheduled to investigate Ivan
about 24 hours from now. By then, it may in all likelihood be a cat. 5
hurricane, as there is not much of anything that would bring a stop to its
rapid intensification. It wouldn't hurt to say a prayer for the safety of
the Hurricane Hunters and NOAA scientists that fly into these storms. 16
years ago, the first plane to investigate Hurricane Hugo was nearly lost
(you can read the story at:

The potential effects of Ivan could be indeed terrible. The first island in
the path is Barbados, where appoximately 278,000 people live. Under the
current track forecast, the storm may pass between Saint Lucia (pop.
164,000) and St. Vincent and the Grandines (pop. 117,000), sparing either
the deadly core (hurricane-force winds are only 35 miles across). Of course,
a slight deviation could produce a direct hit for either of these island
groups. The confidence in this forecast is quite high, and Barbados should
prepare as best as possible for a direct hit from a cat. 5 hurricane 36
hours from now. After passing the windward islands, the forecast track of
Ivan takes it over Hispanola, one of the poorest and most vulnerable areas
you could find (just this year, extreme flooding from an early season
tropical disturbance killed approximately 2000 people there). The extreme
rains are caused by mountains that reach up to 10,414 feet (and the
deforestation). Hispanola has torn apart many mighty storms in the past
(David, Cleo, Inez). It is still too early to say if this will tame Ivan, or
whether Ivan will even pose a threat to the United States. Regardless of the
ultimate effects of Ivan on the U.S., trouble is rapidly approaching the

At 03Z, Ivan was at 10.8N  49.4W, moving west-northwest at 18 kt, with
estimated maximum sustained winds at 115 kt and estimated minimum central
pressure of 948 mb. 

Please visit my tropical Atlantic headquarters.

04 September 2004

Frances crawls ashore east Florida coast, Ivan strengthens...

From Jonathan Vigh: 
Yesterday, Hurricane Frances was lashing Grand Bahama Island on her way
towards Florida. Today, she was still crossing that island! A C-MAN station
on the west part of the island was in the eye for approximately 10 hours
today. The eastern part of the eyewall has finally crossed over that end of
the island and the wind has picked back up to gusts of 80 kts. Currently,
Frances is coming ashore between West Palm Beach and Fort Pierce. Her exact
point of landfall doesn't matter very much because her eye is 70 miles
across! Yesterday's episode of vertical wind shear and dry air disrupted her
core long enough to let the wind field spread out. Storms often have trouble
regrouping once they have a broad wind field because it is hard to spin up
the central part of the storm. The shear appears to have let up somewhat
today, and deep thunderstorms have wrapped all the way around the center of
Frances, forming a very large eye. Within the eye, a weak circulation
appears to be trying to organize as well, but it is doubtful that this will
have much of an effect before landfall. One mechanism which could possibly
help tighten up the core of Frances (leading to intensification) is the
friction with the Florida coast. As the eyewall has been starting to move
onshore this evening, the eye deformed a bit, becoming elliptical for a
while. The greater friction over land may have helped contract the eye by be
helping to squash the eye in the east-west direction, which may help it
contract. On her current pace, the eye of Frances should be completely
onshore in 5-12 hours. This will bring a halt to any possible
intensification -- for a little while. If the eye remains at the current
size, when the eastern end finally moves onshore, the western end will be
most of the way to the other side of Florida!  

Sometime tomorrow morning, Frances should start moving at a more respectable
pace as a trough weakens the ridge that has been blocking her path. She is
likely to finish crosssing Florida by tomorrow night and reemerge out into
the Gulf of Mexico as a tropical storm (this means that most of Florida's
west coast will get tropical storm conditions, including Tampa which was
missed by Charley three weeks ago). Some restregthening is possible, and
then Frances will likely make her 2nd (and final) landfall in the Florida
Panhandle. By the time this event is over, nearly all of Florida will likely
have experienced at least tropical storm force winds and large amounts of

Many of the reporting stations in the immediate vicinity of landfall have
stopped reporting, likely due to power outages. Most of the wind reports
thusfar have been fairly consistent with a category 1 hurricane, but there
have been very few reports since the eyewall actually started moving onshore
a few hours ago. Up till this afternoon, the highest wind report was 91 mph
at Juper River Inlet and 90 mph near West Palm Beach. The outer rainbands
have also packed a punch, causing scattered damage and some power outages as
far south as Miami, as far west as Tampa, and as far north as Orlando and
Daytona Beach. At least 1.1 million customers are now without power and this
number will rapidly grow as the night goes on. 

At 03Z, Frances was at 27.1N  79.7W, moving west-northwest at 5 kt with
maximum susatined winds at 90 kt, and a minimum central pressure of 960 mb. 

Frances will still be with us for several more days, but five days from now,
Ivan may take the spotlight. The storm strenthened today, looking better and
better in the satellite imagery. Ivan is nearly to hurricane stength, and
with low shear and warm waters for at least the next 3 days, there is not
much to keep the storm from steadily strengthening. The forecast calls for
Ivan to cross the central Windward Islands in a little over 3 days, possibly
hitting Hispanola at 5 days as a major hurricane. It is still too soon to
say, but Ivan may pose an additional threat to storm-weary Florida in a
little over a week from now. 

At 03Z, Ivan was at 9.4N  42.4W, moving westward at 16 kt, with estimated
maximum sustained winds at 60 kt and a minimum central pressure of 991 mb.

For other information including preliminary wind and damage reports, see

Please visit my tropical Atlantic headquarters.

03 September 2004

Weaker Frances strolls towards Florida, Ivan named, gaining strength...

From Jonathan Vigh: 
Tropical Storm Ivan became the 9th named tropical storm of the season today.
With a beautiful curved band wrapping into the storm and excellent outflow,
it is easy to see that Ivan is a tropical cyclone with ambition. This
afternoon's visible satellite imagery showed a fascinating thin cloud line
stretching back to Africa -- this curved line, sometimes called the
'umbililcal cord', is due to the convergence of the circulation of the storm
with a surge of low-level easterlies out of Africa's Sahel region. These
Sahel surges, which often contain Saharan dust, are characterized by warm,
stable, dry air which can be detrimental to developing systems. Ivan doesn't
seem to be minding so far, and the storm is forecast to cross the central
Windward Islands in less than 5 days as a major hurricane. 

At 21Z, Ivan was at 8.9N  34.6W, moving west-southwest at 19 kts. Maximum
sustained winds were estimated at 45 kt and the lowest central pressure was
estimated at 1000 mb.

It appears that there were some chinks in Frances' armor. The storm came
under some moderate westerly vertical wind shear starting yesterday. The
cause of this shear is not obvious, but rather due to subtle changes in the
environment. First of all, the upper level winds changed from light
southeasterly (moving with the storm) to light southwesterly (moving against
the storm). This wouldn't be enough to cause the disruption that has
resulted, however, so there's more to the story. At the same time, the ridge
to the north of the storm built around to the northwest of the storm as
well, slowing it down to a crawl. The low level steering flow behind Frances
didn't know about this, and continued trying to push the storm
northwestward. With the combination of the upper level winds and the pushing
from below, the shear has become considerable, stressing the storm. Along
with the unfavorable winds, Fracnes ingested a large amount of dry air from
the west. In just a few hours' time, the convection died out on the
southwest side of the storm and the circulation started slowing down. It
takes a long while to slow down a cat. 4 hurricane, and it wasn't until this
evening that the winds dipped down to cat. 2 strength. Unfortunately, the
hurricane is sitting directly over the northwest Bahamas, continuing to lash
these islands with sustained winds as high as 100 mph at times. Yesterday,
as she passed over San Salvador Island, Frances caused wind gusts up to 152
mph! Today, there have been several reports of sustained winds to 100 mph on
Eleuthera and Great Abaco Island (which also reported gusts to 115 mph).
Nassau, the capital of the Bahams, recently reported a gust to 110 mph, and
this is on the weak side of the storm, so Frances still packs a punch.   

Frances is forecast to move very slowly towards the west or northwest over
the next day, finally making landfall in Florida sometime tomorrow afternoon
or evening. Although the core of the hurricane is weaker, the outer
circulation is still very broad and capable of spreading hurricane force
winds over a large area. Because of this, winds to at least tropical storm
force could still be felt from south of Miami up to the Georgia border. The
outer rain bands have started to reach eastern Florida this evening, and
have been strong enough to knock down trees and cause isolated power
outages. People in the hurricane warning area should not let their guards
down, as a cat. 2 hurricane can still cause death and destruction. If the
shear lets up a bit, it is quite possible that Frances could gain strength
again. The massive bursts of convection blowing up right over the center of
the storm are a sign that the Frances still has spunk. If Frances crosses
Florida the short way, she could reemerge into the Gulf to cause more
trouble there early next week.    

At 00Z, Frances was at 25.9N 77.5W, moving very slowly towards the
west-northwest with maximum sustained winds of 90 kt and a minimum central
pressure of 960 mb.

For more Frances links and information including storm surge maps, local
weather statements, and technical information on Frances, please see

Please visit my tropical Atlantic headquarters.

02 September 2004

Frances pounds the Bahamas, eyes Florida, 9th Depression of the season forms...

From Jonathan Vigh: 
The 9th Tropical Depression of the season formed this afternoon a few
hundred miles southwest of the Cape Verde Islands. This system came off
Africa a couple days ago and has possessed deep convection for at least
the last 36 h. Healthy outflow was spreading out in all directions even
before the system received a number, and it appears to be in low shear.
Its relatively low latitude and a lack of any immediate troughs will
allow this system to traverse the Atlantic fairly undisturbed for the
next 5 days. The official forecast calls for a 70 kt hurricane near
Barbados in 5 days. 

At 21Z, Tropical Depression 9 was at 9.7N  29.1W, moving towards the
west at 17 kt, with winds of 25 kt and an estimated central pressure of
1009 mb.

Meanwhile, Hurricane Francis is currently rampaging through the Bahamas
and targeting the central Florida east coast. The storm's southern
eyewall passed a little to the north Grand Turk Island in the middle of
the night. Sustained winds were clocked at 79 mph, which caused damage
to roofs trees. An hour or two ago, the eye passed directly over the
small, but populated island of San Salvador. Winds rapidly climbed to a
sustained 114 mph (with higher gusts). Long Island is next, followed by
Cat Island and Eleuthera (this island was strongly affected by Hurricane
Andrew in 1992). Unfortunately, nearly all the Bahaman Islands will be
affected by this storm. About 300,000 people live in the Bahamas, and
nearly all of them are going to experience some portion of this storm
(it is hard to evacuate from an island for obvious reasons). 

Frances weakened somewhat this morning, with the central pressure rising
to 949 mb. Winds have decreased slightly to 120 kt. There was an
apparent disruption to the eye, which was open for a while this morning.
Perhaps this was another eyewall cycle, or even a bit of vertical wind
shear. The appearance on satellite is not quite as good as in recent
days -- the storm is a little ragged and somewhat asymmetrical, but very
deep convection is still blowing up in the eyewall. With continuing low
shear, extremely warm Gulf Stream waters (as warm as 88 deg F along the
coast!), and less dry air in the environment, there is at least a chance
the storm will strengthen before landfall. More eyewall cycles could
cause weakening, but it is highly likely that Frances will hit as a
major hurricane.

Where will Frances hit is the next question to answer. The global and
regional models used by hurricane forecasters have tightly clustered on
the central Florida coastline. The most likely place to experience the
core of the storm is anywhere from West Palm Beach up to Vero Beach. But
the storm could still hold surprises in the track department (remember
Charley?), so a hurricane warning has been issued for the entire
coastline from Florida City (south of Miami) to Flagler Beach (near
Daytona Beach). Even if the forecast is dead on, a large section of the
warning area will likely see hurricane force winds because of the size
of the storm. Any significant deviation in the track could still bring
the area of hurricane force winds further north or south, but that looks
unlikely at this point. It is very important for everyone in the warning
area to heed the directions of local emergency officials. People that
live in low-lying areas or mobile homes should NOT stay in their homes.
About 1.2 million people fit in this category and have been told to
evacuate to safer locations. Also, remember that the high winds of a
hurricane can extend well inland past the coast. Hurricane force winds
can be felt as far inland as 150 miles or more in a strong, fast moving
storm -- as Charley showed in the Orlando area. Frances is forecast to
turn northwestward over Florida and weaken to tropical storm force about
half a day after landfall. If it stays further west, it could cross
Florida and restregthen in the Gulf of Mexico before a second landfall
in the Florida Panhandle. Thus, residents as far west as Mobile, Alabama
should keep an eye on this storm over the weekend. 

At 21Z, Frances was located about 375 miles east-southeast of the lower
Florida East Coast, at 24.1N  74.8W, moving towards the northwest near 9
kt. Maximum sustained winds were at 120 kt and the minimum central
pressure was 946 mb. 

Please visit my tropical Atlantic headquarters.

01 September 2004

Frances a major threat to most of Florida, Gaston becomes extratropical...

From Jonathan Vigh: 
Early this morning, the NHC wrote the last advisory on Gaston as the
system transitioned to extratropical status. Healthy winds will be
experienced to the right of the storm as it passes south of Newfoundland
into the open Atlantic. 

A couple of disturbances have come off of Africa in the past couple
days. One of these passed over the Cape Verde Islands and is moving into
the Atlantic at about 18N. The other has just come off of Africa and is
much further south, around 9N. Both have a chance of developing, but the
smart money is probably on the southern system. If it develops, it will
be named Ivan. 

Frances now poses a major threat to the southern East Coast of the
United States. The storm is currently passing just to the north of the
Turks and Caicos Islands, and is forecast to pass through the Central
Bahamas on a track towards Florida's east coast. The storm is still
being steered by a strong ridge to the north, and right now, most of the
forecast models keep the ridge in a configuration that would force the
storm to make landfall somewhere in Florida. The forecast is still
uncertain, and depends somewhat on a trough over the Western U.S. A
stronger, deeper trough would likely strengthen the ridge north of
Frances, forcing her to make landfall further south and west. A weaker,
faster trough could weaken the ridge and allow Frances to drift further
north before landfall -- this scenario would keep Northern Florida,
Georgia, and even South Carolina at risk. Potential landfall is still at
least 72 hours away (as soon as Saturday morning), but it is looking
more and more likely that Florida will bear the brunt of this storm.
Residents of Georgia and even South Carolina should still closely
monitor the progress of this storm however, because it would not take
much of a turn to bring the storm close enough for ill effects to occur.
All people in the potential risk area should remember that the storm is
not a point -- at landfall, Frances' hurricane-force winds could extend
out up to 120 mile from the center. This means that wherever she hits, a
large portion of coast will be affected. 

As in previous days, very interesting changes to the inner core have
been occurring, with eyewall cycles taking place roughly every 12 hours.
As of this afternoon, it appears that another eyewall cycle was
completing, leaving a large 30 nm eye. The eye will probably contract
soon, potentially strengthening the storm. The outflow is excellent,
with two well defined outflow channels to the north and south. The storm
has been modifying its own environment -- the upper level low to the
west of Frances has been filling and weakening with time, allowing the
storm to stay in a favorable low shear environment. Thus, no external
influences are likely to cause any drastic weakening of the storm before
landfall. If anything the storm could strengthen as it passes over the
very warm waters of the Gulf Stream, and is very likely to make landfall
with at least cat. 3 intensity. 

To have two cat. 4 hurricanes make landfall in the same state within a
month would be unprecedented. Sadly, areas that were walloped by
Charley, such as the Orlando area (which had at least $3 billion worth
of damage), may experience even more devastation from Frances. Most of
the Florida coast is very populated, so it would be very difficult for
this storm not to produce a tremendous amount of damage, possibly
comparable to the damage produced by Hurricane Andrew. Even the Tampa
Bay area could experience hurricane conditions under some track
scenarios. Anyone living in main part of Florida or southeast Georgia
should closely monitor this storm and keep an ear to local officials for
actionable statements. 

I have prepared a Frances-themed resource page with links to local
radars, satellite loops, and other storm information (some of these are
quite technical), which can be accessed at:

Please visit my tropical Atlantic headquarters.