ATL: TROPICAL DEPRESSION CLAUDETTE (04L)

[yzerfan]

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

This one reminds me of a slightly stronger version of TD 10 in 2007, so in other words not a whole lot of much other than a bit of coastal flooding. Probably a slightly windier version of the usual summer thunderstorms we get.

[MGC]

Thankfully TD 4 will be inland soon giving it little time to intensify. Might make it to minimal TS intensity. I was fun last night watching a TC form on radar....MGC

[bob rulz]

Recon will definitely be very interesting to track today.

[wxman57]

Here's a surface plot showing the west wind at buoy 42036. Lowest pressure at the buoy was above 1013mb. Pressures along the western FL peninsula are 1018-1019mb - about a 5mb drop. That's the reason for winds 20-25 kts east of the center. The squalls will have stronger winds than that, though. Little to nothing west of the center.

[drezee]

Chicken Dinner:

(EDT) WDIR WSPD
9:50 am W ( 265 deg ) 8.2 kts
9:40 am WNW ( 288 deg ) 9.1 kts
9:30 am NW ( 320 deg ) 8.9 kts
9:20 am NNW ( 341 deg ) 9.7 kts
9:10 am NNW ( 340 deg ) 9.3 kts
9:00 am NNW ( 330 deg ) 9.5 kts

I am a bit surprised it turned S of due W so quickly...may be indicate a slight NW turn.

[Thunder44]

ADT has T# 2.5 now. But I think NHC is more likely to wait for recon to upgrade:

Code: Select all

         UW - CIMSS                     
              ADVANCED DVORAK TECHNIQUE       
                  ADT-Version 7.2.3               
         Tropical Cyclone Intensity Algorithm       

             ----- Current Analysis -----
     Date :  16 AUG 2009    Time :   131500 UTC
      Lat :   28:31:13 N     Lon :   84:26:17 W

     
                CI# /Pressure/ Vmax
                2.5 /1005.0mb/ 35.0kt

     
             Final T#  Adj T#  Raw T#
             (3hr avg)               
                2.5     2.8     2.9

     Latitude bias adjustment to MSLP :  +0.0mb

 Center Temp : -52.4C    Cloud Region Temp : -51.2C

 Scene Type : UNIFORM CDO CLOUD REGION

 Positioning Method : FORECAST INTERPOLATION

 Ocean Basin : ATLANTIC     
 Dvorak CI > MSLP Conversion Used : ATLANTIC 

 Tno/CI Rules : Constraint Limits : 0.2T/hour
                   Weakening Flag : OFF   
           Rapid Dissipation Flag : OFF   

http://cimss.ssec.wisc.edu/tropic2/real ... dt04L.html

[MGC]

So, no doubt about a surface circulation....MGC

[KWT]

Hmm the risk with waiting for recon is it won't get there in time, only needs for it to speed up a touch and then it'll be too late.

No doubt its got a LLC, looks tiny however!

[Emmett_Brown]

Easterly breezes increasing here in NE FL off the Atlantic. No doubt there is a storm near by judging from increasing breeze and low clouds moving more briskly. Feels great!

[drezee]

I beleive it has no choice but to turn NW. A surface trough is clear on the surface reports SW of the big bend (you can tell by the SE winds offshore W of due North of the center). Typically a small system like this will follow such a trough up to the coast. If this is the case, it will be closer to Panama City than Tallahasee, IMO. This is basically the same thing Humberto did last year...(not the same result though). Using Wxman57's GARP, I would say passes N of the trough axis as show, but it has a chance to stay over the water as the trough is over the water...

[cycloneye]

622
WTNT34 KNHC 161435
TCPAT4
BULLETIN
TROPICAL DEPRESSION FOUR ADVISORY NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042009
1100 AM EDT SUN AUG 16 2009

...DEPRESSION APPROACHING TROPICAL STORM STRENGTH...AIRCRAFT
RECONNAISSANCE WILL INVESTIGATE SOON...

A TROPICAL STORM WARNING REMAINS IN EFFECT FROM THE ALABAMA/FLORIDA
BORDER EASTWARD TO THE SUWANNEE RIVER FLORIDA. A TROPICAL STORM
WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED SOMEWHERE
WITHIN THE WARNING AREA WITHIN 24 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA IN THE UNITED
STATES...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE
MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE
FORECAST OFFICE. FOR STORM INFORMATION SPECIFIC TO YOUR AREA
OUTSIDE OF THE UNITED STATES...PLEASE MONITOR PRODUCTS ISSUED
BY YOUR NATIONAL METEOROLOGICAL SERVICE.

AT 1100 AM EDT...1500 UTC...THE CENTER OF TROPICAL DEPRESSION FOUR
WAS LOCATED NEAR LATITUDE 28.7 NORTH...LONGITUDE 84.6 WEST OR ABOUT
75 MILES...120 KM...SOUTH-SOUTHEAST OF APALACHICOLA FLORIDA AND
ABOUT 200 MILES...320 KM...SOUTHEAST OF PENSACOLA FLORIDA.

THE DEPRESSION IS MOVING TOWARD THE NORTHWEST NEAR 14 MPH...
24 KM/HR. THIS MOTION IS EXPECTED TO CONTINUE TODAY...AND ON THE
FORECAST TRACK THE CENTER WILL BE NEAR THE NORTHERN GULF COAST OF
FLORIDA BY THIS EVENING.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/HR...WITH HIGHER
GUSTS. SOME STRENGTHENING IS EXPECTED...AND THE DEPRESSION IS
FORECAST TO BECOME A TROPICAL STORM PRIOR TO REACHING THE
COASTLINE.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1011 MB...29.85 INCHES.

RAINFALL ACCUMULATIONS OF 3 TO 5 INCHES...WITH ISOLATED MAXIMUM
AMOUNTS OF 10 INCHES ARE EXPECTED ACROSS THE FLORIDA PANHANDLE...THE
BIG BEND REGION OF FLORIDA...SOUTHERN ALABAMA...AND SOUTHWESTERN
GEORGIA NEAR THE PATH OF THE CENTER.

STORM TIDE IS EXPECTED TO PRODUCE MAXIMUM WATER LEVELS OF 3 TO 5
FEET ABOVE GROUND LEVEL ALONG PORTIONS OF THE FLORIDA PANHANDLE...
INCLUDING THE BIG BEND.

...SUMMARY OF 1100 AM EDT INFORMATION...
LOCATION...28.7N 84.6W
MAXIMUM SUSTAINED WINDS...35 MPH
PRESENT MOVEMENT...NORTHWEST OR 320 DEGREES AT 14 MPH
MINIMUM CENTRAL PRESSURE...1011 MB

AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE
CENTER AT 200 PM EDT FOLLOWED BY THE NEXT COMPLETE ADVISORY AT 500
PM EDT.

$$
FORECASTER BRENNAN/ROBERTS



WTNT44 KNHC 161437
TCDAT4
TROPICAL DEPRESSION FOUR DISCUSSION NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042009
1100 AM EDT SUN AUG 16 2009

VISIBLE SATELLITE IMAGERY AND DATA FROM THE TAMPA WSR-88D INDICATE
DEVELOPING DEEP CONVECTIVE BANDING OVER THE EAST SEMICIRCLE OF THE
TROPICAL CYCLONE. IT APPEARS THAT THE WINDS ASSOCIATED WITH THE
STRONGER BANDS MAY NOT YET BE MIXING DOWN TO THE SURFACE...AS NOAA
BUOY 42036 LOCATED JUST TO THE NORTH-NORTHWEST OF THE CIRCULATION
CENTER IS REPORTING WINDS OF LESS THAN 15 KT. AIRCRAFT
RECONNAISSANCE WILL BE INVESTIGATING THE CYCLONE SHORTLY TO HELP
DETERMINE IF IT HAS BECOME A TROPICAL STORM.

ALTHOUGH REGIONAL UPPER-AIR SOUNDINGS AND WATER VAPOR IMAGERY
SUGGEST THAT THE THERMODYNAMIC ENVIRONMENT IS ONLY MARGINALLY
FAVORABLE...THE UPPER-LEVEL SOUTHERLY FLOW OVER THE DEPRESSION IS
QUITE DIFFLUENT. CONSEQUENTLY...THE OFFICIAL INTENSITY FORECAST
STILL REFLECTS STRENGTHENING JUST BEFORE LANDFALL. AFTER THAT
TIME...WEAKENING AND DISSIPATION IS FORECAST WITHIN 48 HOURS AS THE
SYSTEM MOVES INLAND OVER THE NORTHERN GULF COAST.

THE INITIAL MOTION IS 330/13. THE CYCLONE IS MOVING AROUND THE
PERIPHERY OF THE SUBTROPICAL RIDGE AND IS EXPECTED TO MAINTAIN THIS
APPROXIMATE HEADING UNTIL LANDFALL. THE OFFICIAL FORECAST IS CLOSE
TO A CONSENSUS OF A FAIRLY TIGHTLY CLUSTERED GUIDANCE SUITE.

ALTHOUGH THE DEPRESSION IS VERY SMALL AND HAS A LIMITED WIND
FIELD....HEAVY RAINFALL IS LIKELY NEAR THE TRACK OF THE CYCLONE
ACROSS THE FLORIDA PANHANDLE...SOUTHWESTERN GEORGIA AND SOUTHERN
ALABAMA.

FORECAST POSITIONS AND MAX WINDS

INITIAL 16/1500Z 28.7N 84.6W 30 KT
12HR VT 17/0000Z 30.2N 85.8W 50 KT
24HR VT 17/1200Z 32.1N 87.1W 35 KT...INLAND
36HR VT 18/0000Z 34.0N 88.2W 20 KT...DISSIPATING INLAND
48HR VT 18/1200Z...DISSIPATED

$$
FORECASTER BRENNAN

[cyclonic chronic]

i agree thunder44. they'll wait till recon confirms or denies a T.S. As for being too late, they already have warnings up. also the difference between a depression and a 40-50mph T.S. isnt big and its so small that if it is a T.S., those sustained winds will be confined to a tiny area of the coast, if at all. of course it could go crazy and really ramp up, mother nature has been know to suprise us a time or two before.

[Dionne]

"Resources permitting".....? I suppose we'll find out in about 20 minutes?

[aOl]

11AM EDT discussion now strengthens it to a 60mph TS. Looks like NHC has Humberto on their minds and wants to make sure they don't get burned again.

[KWT]

Yep, much depends on its exact track as well, if it can get west of 86 then its got a little bit more in the way of real estate and remember its such a small center that it doesn't need much space.

I do think the NHC are too slow but the 50kts probably isn't a bad call.

[bob rulz]

11AM EDT discussion now strengthens it to a 60mph TS. Looks like NHC has Humberto on their minds and wants to make sure they don't get burned again.

Where in the world did you get that? It's still a tropical depression...

[Dionne]

??????? The 11AM advisory from NHC doesn't show those numbers?

[bob rulz]

Oh, you're talking about at landfall.

It was hard to tell from the way you worded it...my bad.

[senorpepr]

"Resources permitting".....? I suppose we'll find out in about 20 minutes?

Based upon the 15Z advisory, it looks like the mission is a go.

[MGC]

Still a TD at 10am advisory......MGC