26 September 2002

Isidore makes landfall, Kyle makes hurricane, Lili downgraded to TD.

Isidore made landfall today at about 2am CDT on Port Fourchon, LA (about
75 miles south of New Orleans) as a 55kt Tropical Storm.  Since there
was no eyewall, the exact location doesn't matter too much; the storm is
huge and all surrounding states will feel roughly the same effects
(something I emphasized during a -unexpected- radio interview with
Denver's KOA News Radio yesterday morning, along with the inland
flooding potential).  At 15Z, TS Isidore was located at 30.7N 89.7W and
tracking NNE at 12kts.  This motion will accelerate with time as it
merges with a trough.  Intensity is 50kts and 985mb.  Further weakening
is expected as the storm is now over land and being sheared by that

The storm surge on the east side of the center was moderate, 3-6' above
tides in most areas, then about 10' above tides in the more shallow
bays.  Keep in mind that a good portion of southern LA is at or below
sea level in the first place. In addition to the storm surge, places
along the central Gulf coast will receive on the order of 2 feet of rain
from Isidore.  Also, there have already been several tornadoes
associated with the Tropical Storm, though I believe there have not yet
been any injuries or deaths.

Tornado Watches and Warnings cover parts of LA, MS, AL, FL, and GA and I
suspect the watches will be shifted north as the rainbands move further
inland.  There are Coastal Flood Watches and Warnings along those same
states; Tropical Storm Warnings for eastern LA, MS, AL, and the FL
panhandle; and Flood Watches for every state from the Gulf coast up to
New England, including LA, MS, AL, FL, GA, TN, KY, IN, OH, PA, and NY. 
People at highest risk for tropical cyclone-spawned tornadoes are those
living in eastern MS, southern TN, all of AL, western GA, and the
western FL panhandle.  This would be a good day for everyone in the
states mentioned in this section to keep a local radio station or TV
channel on just in case action is required, whether it's involving a
tornado or a flash flood.  http://www.spc.noaa.gov/products/wwa/ is a
good source for monitoring the Watches and Warnings, but should not
replace local broadcasts from your NWS office.

Yesterday at 21Z, Kyle was upgraded to a hurricane, the third of the
season.  The satellite signature is fairly good; there's a small ragged
eye that microwave, visible, and infrared imagery all pick up, but the
convection is not very deep (cloud tops aren't very cold).  The drift to
the SW over warmer SSTs has made all the difference, but he exists in a
small patch of the Atlantic where the vertical shear is favorable for
the development of a small storm.  At 15Z today, he was at 27.8N 58.7W
(770km SE of Bermuda) and heading WSW at 8kts.  Maximum sustained winds
are 75kts and the MSLP is 980mb.  Only slight strengthening is possible
in the short term before an advancing trough introduces higher shear. 
Of course, as you're probably envisioning, he's already completed one
loop, and now he's heading SW, but a trough is coming, so he'll turn
back NE ahead of it.  By the time he's done, it will be an interesting
track to look at!

Lili was downgraded to a TD today at 15Z and the last advisory has been
issued, unless regeneration occurs (which could very well happen).  An
aircraft in the storm was unable to find a defined low-level center, and
the convection has been somewhat disorganized.  Her position at 15Z was
15.2N 72.5W (roughly halfway between Colombia's Guajira Peninsula and
Haiti), winds were reported as 30kts with 1006mb central pressure. 
Redevelopment is forecast on Sunday morning just south of the western
tip of Cuba as she heads into the same area that Isidore did when he
became a hurricane... between the Yucatan Peninsula and Cuba, perhaps
entering the Gulf by Monday afternoon.

Please visit my tropical Atlantic headquarters.

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