ATL: DEBBY - Post-Tropical

[Pearl River]

000
WTNT24 KNHC 232051
TCMAT4

TROPICAL STORM DEBBY FORECAST/ADVISORY NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL AL042012
2100 UTC SAT JUN 23 2012

CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

A TROPICAL STORM WARNING HAS BEEN ISSUED FROM THE MOUTH OF THE PEARL
RIVER WESTWARD TO MORGAN CITY LOUISIANA...NOT INCLUDING THE CITY OF
NEW ORLEANS OR LAKE PONTCHARTRAIN.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* THE COAST OF LOUISIANA FROM THE MOUTH OF THE PEARL RIVER WESTWARD
TO MORGAN CITY...NOT INCLUDING THE CITY OF NEW ORLEANS OR LAKE
PONTCHARTRAIN

[Evil Jeremy]

The pressure is all on the EURO now.

[Jevo]

I wouldn't say they went primarily with the EURO. The 12z HWRF has a similar solution.

[marciacubed]

Anyone here surprised the NHC went withe Euro???

[gatorcane]

Wow. NHC went with the Euro model primarily. That was unexpected.

Yes very unexpected. Also a very short discussion as expected from Avila. Would have thought they would not commit to west or east yet. It's rare the NHC goes completely against the GFS operational. Cant remember the last time they did that.

[JtSmarts]

Looks like the official forecast is very similar, almost identical to the UKMET listed in the spaghetti plots.

[Ivanhater]

Wow..did not expect that....the discussion should be interesting

[Kingarabian]

Here is the disco:
(Please don't quote this post )

000
WTNT44 KNHC 232052
TCDAT4

TROPICAL STORM DEBBY DISCUSSION NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL AL042012
400 PM CDT SAT JUN 23 2012

AIRCRAFT RECONNAISSANCE...SATELLITE...AND BUOY DATA INDICATE THAT
THE CIRCULATION ASSOCIATED WITH THE AREA OF LOW PRESSURE IN THE
GULF OF MEXICO HAS BECOME SUFFICIENTLY DEFINED TO CLASSIFY THIS
SYSTEM AS A TROPICAL STORM. THE INITIAL INTENSITY IS BASED ON A
HIGHEST 1000-FT FLIGHT-LEVEL WIND OF 61 KT AND SFMR WINDS NEAR 45
KT. THESE WINDS ARE ONLY OCCURRING TO THE EAST OF THE CENTER.

DEBBY IS MOVING SLOWLY NORTHWARD...OR 360 DEGREES AT 5 KT. THE
CYCLONE IS IN A WEAK STEERING ENVIRONMENT BETWEEN TWO MID-LEVEL
RIDGES LOCATED OVER THE GREATER ANTILLES AND THE SOUTHERN UNITED
STATES...AND DEBBY IS NOT EXPECTED TO MOVE MUCH DURING THE NEXT
COUPLE OF DAYS. THE TRACK GUIDANCE IS SPLIT IN TWO BRANCHES...WITH
THE GFS AND GFDL SHOWING AN EASTWARD MOTION ACROSS FLORIDA...AND
THE REST OF THE MODELS BRINGING DEBBY WESTWARD ACROSS THE NORTHERN
GULF TOWARDS TEXAS. EVEN THOUGH THE DETERMINISTIC GFS SHOWS AN
EASTWARD TRACK...MORE THAN HALF OF THE GFS ENSEMBLE MEMBERS ARE IN
AGREEMENT WITH THE WESTWARD-MOVING MODELS...MAKING THE WESTWARD
SCENARIO SEEM MORE LIKELY. IT IS IMPORTANT TO NOTE TOO THAT THE
ECMWF MODEL SHOWS A FASTER WESTWARD MOTION THAN INDICATED IN THE
NHC FORECAST...SO IT IS POSSIBLE THAT DEBBY COULD REACH THE COAST
EARLIER THAN INDICATED.

DEBBY IS CURRENTLY A SHEARED CYCLONE WITH NEARLY ALL OF THE DEEP
CONVECTION LOCATED IN A CURVED BAND TO THE EAST OF THE CENTER.
HOWEVER...AN UPPER-LEVEL LOW OVER THE NORTHWESTERN GULF OF MEXICO
IS FORECAST TO DIG SOUTHWESTWARD...WHICH WILL RESULT IN A DECREASE
OF VERTICAL SHEAR AFFECTING THE SYSTEM...AND A GREATER CHANCE OF
INTENSIFICATION OVER THE NEXT FEW DAYS. BECAUSE THE OFFICIAL TRACK
FORECAST IS SO DIFFERENT FROM THE GFS SOLUTION...THE GFS FIELDS USED
BY THE SHIPS AND LGEM MODELS ARE NOT LIKELY TO BE REPRESENTATIVE OF
THE CONDITIONS ENCOUNTERED BY DEBBY. THE NHC FORECAST THEREFORE
SHOWS MORE STRENGTHENING THAN INDICATED BY THE INTENSITY GUIDANCE.

DEBBY IS THE EARLIEST 4TH STORM IN THE HISTORICAL RECORDS...
SURPASSING HURRICANE DENNIS OF 2005...WHICH BECAME A TROPICAL STORM
ON JULY 5TH.


FORECAST POSITIONS AND MAX WINDS

INIT 23/2100Z 26.2N 87.6W 45 KT 50 MPH
12H 24/0600Z 26.9N 87.8W 45 KT 50 MPH
24H 24/1800Z 27.3N 88.1W 50 KT 60 MPH
36H 25/0600Z 27.4N 88.5W 50 KT 60 MPH
48H 25/1800Z 27.5N 89.5W 55 KT 65 MPH
72H 26/1800Z 27.5N 91.5W 55 KT 65 MPH
96H 27/1800Z 27.5N 93.5W 60 KT 70 MPH
120H 28/1800Z 27.5N 95.0W 60 KT 70 MPH

$$
FORECASTER BERG/AVILA

[Dave]

[bella_may]

I sure hope the NHC is not eating crow tomorrow morning

[Dave]

000
URNT15 KNHC 232056
AF302 01AAA INVEST HDOB 32 20120623
204900 2810N 08500W 9627 00423 //// +215 //// 126040 040 027 004 01
204930 2812N 08500W 9627 00423 //// +210 //// 127038 040 027 004 01
205000 2814N 08500W 9631 00420 //// +207 //// 127039 040 024 004 01
205030 2816N 08500W 9632 00418 //// +207 //// 128037 038 023 004 01
205100 2817N 08500W 9629 00422 //// +206 //// 131039 040 027 004 01
205130 2819N 08500W 9628 00423 //// +206 //// 130040 042 026 005 01
205200 2821N 08500W 9632 00420 //// +206 //// 130041 042 025 006 05
205230 2822N 08502W 9625 00428 //// +209 //// 128038 041 /// /// 05
205300 2821N 08503W 9630 00421 //// +207 //// 128036 037 022 006 01
205330 2819N 08504W 9630 00420 //// +209 //// 126034 036 022 005 01
205400 2818N 08505W 9628 00422 //// +208 //// 124034 035 022 004 01
205430 2817N 08507W 9632 00418 //// +210 //// 123035 036 023 002 01
205500 2816N 08508W 9629 00419 //// +208 //// 122035 035 024 003 01
205530 2815N 08509W 9629 00419 //// +210 //// 120036 037 023 002 01
205600 2814N 08511W 9629 00418 //// +210 //// 121036 036 022 004 01
205630 2813N 08512W 9630 00417 //// +211 //// 123037 037 022 004 01
205700 2812N 08513W 9627 00419 //// +210 //// 122037 038 027 003 01
205730 2811N 08515W 9629 00416 //// +215 //// 124038 039 025 003 01
205800 2810N 08516W 9629 00416 //// +215 //// 123038 039 027 003 01
205830 2808N 08517W 9631 00412 //// +215 //// 123039 040 026 003 01
$$
;

[Kingarabian]

Looks like we finally have a drought buster for TX!

[Texas Snowman]

From NHC discussion:

"EVEN THOUGH THE DETERMINISTIC GFS SHOWS AN
EASTWARD TRACK...MORE THAN HALF OF THE GFS ENSEMBLE MEMBERS ARE IN
AGREEMENT WITH THE WESTWARD-MOVING MODELS...MAKING THE WESTWARD
SCENARIO SEEM MORE LIKELY."

[wkwally]

Hello Debbie. Well from what I am seeing with the NHC I really need to gear up could be in for a long week

[pgoss11]

Anyone here surprised the NHC went withe Euro???

I am somewhat surprised that they went 100% with the Euro. I honestly thought there might have been a blend of all the models with maybe a Ms/La landfall. The pressure is definitley on the Euro now.. gonna be fun to watch.

[pgoss11]

Anyone here surprised the NHC went withe Euro???

I am somewhat surprised that they went 100% with the Euro. I honestly thought there might have been a blend of all the models with maybe a Ms/La landfall. The pressure is definitley on the Euro now.. gonna be fun to watch.

[AJC3]

They are issuing Small Craft Advisories and heavy surf instead of Tropical Storm watches in the FL Panhandle as of 325PM

URGENT - MARINE WEATHER MESSAGE
NATIONAL WEATHER SERVICE TALLAHASSEE FL
425 PM EDT SAT JUN 23 2012

...SMALL CRAFT ADVISORY REMAINS IN EFFECT 8 AM EDT MONDAY...

.STRONG SOUTHERLY FLOW WILL CONTINUE OVER THE MARINE AREA
WITH THE AREA OF TROPICAL LOW PRESSURE IN THE EAST CENTRAL GULF OF
MEXICO. ADVISORY CONDITIONS WILL CONTINUE THROUGHOUT THE FORECAST
PERIOD WITH SEAS BUILDING TO AS HIGH AS 14 FEET WELL OFFSHORE BY
MONDAY. EXPECT WINDS AND SEAS TO GRADUALLY DECREASE ON TUESDAY
INTO WEDNESDAY AS THE LOW PRESSURE AREA MOVES FURTHER WESTWARD
AWAY FROM THE REGION.

That's because the local NWS offices have no jurisdiction to issue TS watches/warnings for the coast. Only the NHC. Local offices can issue tropical watches/warnings for INLAND counties once the initial watch goes up.

This requires a bit more thorough explanation - while the products come from NHC, they don't unilaterally issue TC watches and warnings. They are proposed to the local NWS forecast offices (FO's) during the coordination calls, and the final say comes through a meeting of the minds, so to speak. Generally the NHC and FO's agree on the breakpoints, but sometimes they don't, and make a "counter-proposal" to NHC.

[Sanibel]

Interesting, those two vortices merged and maintained the larger spiral.

[jlauderdal]

A little humor from Jim Cantore:

"@JimCantore: Who else is as excited as I am to see NHC cone 4 #Debby? Never seen the whole Gulf in a cone B4... Should be interesting to say the least."

private weather services such his employer, accu weather etc. might have a cone for the whole gulf but NHC won't, their cone is based on stats

[Kingarabian]

Well the Euro did really well with the last storm compared to the GFS...

Compared with the Euro, the GFS's credibility is on the line now because it completely busted the last storm...