Tuesday, June 26, 2012

Tropical Storm Debby: June 25, Update B

T.S. Debby is still heading in a northeastward direction and has moved a little since the last update. She is now at 29.2N, 85.1W, just about 35 miles south of Apalachicola in Florida. She has slowed down again from her earlier speedy 3mph to 2mph (steady now, we wouldn’t want to rush anything). Her winds are still 45mph with a central pressure of 992mb, so she’s still a weak TS (range: 39-73mph).

Track: The center of cone shifted slightly to the north from her earlier track, and into the Big Bend area north of Cedar Key. This is reasonable. Landfall has now been shifted forward to Wednesday evening, which is also quite reasonable in my (sometimes) humble opinion. ;-)

Intensity: I don’t know what you guys in the Panhandle/north Florida and southern Georgia were doing this afternoon, but I expect it involved lots of raincoats and wellington boots. These areas had some strong convection north of the center which is weakening now (Rob H. in Atlanta: you asked for rain… did you get any?) – IR satellite image:

Also I see that the circulation is starting to decrease! Hurray! (Although the wind is still howling here. Along with the creaking roof beams it sounds like I’m in some cheesy b/w horror movie.) There is no circulation in the upper troposphere, and the circulation (vorticity) in the lower half of the troposphere has also decreased slightly. This is because the wind shear has increased. I mentioned the other factors inhibiting her development earlier: she is so very close to land; there is dry air in the system; and, there isn’t too much deep warm water under her. I agree with the NHC that she is a weak Tropical Storm.

Storm surge has increased since yesterday along west Florida because water has been pushed onto the coast all day today. The surge above normal tide in St. Petersburg is now just over 3ft, so at high tide this afternoon the water level was almost 5ft. Here is a photo of the road to my work just after high tide:

The water level at Cedar Key is now 4ft above normal, so with high tide earlier this afternoon the water level was over 6 ft. Water levels were higher than usual in southwest Florida too. Fort Myers, for example, had water levels of about 3ft above normal earlier today. Meanwhile, on the other side of the storm the water is now being pushed away from the coast so at Panama City the water level has dropped from 1.5 ft above normal to 1 ft above, and is still decreasing.

Attached is another photo of flooding from Steve M., taken at Coffee Pot Bayou in St. Petersburg from yesterday (thanks Steve!):

Apart from the tornadoes, this really was a water event!

She is now so close to landfall (and yet so far!). Tomorrow I’ll try and figure out what is next for Dillydallying Debby. J Hmm… I don’t think I had any ice cream today. Is it too late to have some as a bedtime snack I wonder? ;-)

Night folks!
J.

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DISCLAIMER: These remarks are just what I think/see regarding tropical storms - not the opinion of any organization I represent. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast and the National Weather Service announcements. This is not an official forecast. If I "run away, run away" (Monty Python), I'll let you know.
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2 comments:

diverdutch said...

Have the ice cream for breakfast.

Anonymous said...

Remarkably sharp and stable bounday between moderate and extreme rainfall here in Panhandle. In Tallahassee, we appreciate the rain (it's been dry) if we live on the northern side, but not so much if on the southern side or further south to the Gulf.
5.5" total here in N. Tally, 10"-20"+ only 10-20 miles south.