ATL : TROPICAL DEPRESSION ERIKA (06L)

[KWT]

and I'm not sure that "zone of death" is going away as fast as GFS says

I agree, I think in this case the ECM is probably going to be closer to the truth with the shear not really easing till the end of the week.

[drezee]

and I'm not sure that "zone of death" is going away as fast as GFS says

I agree, I think in this case the ECM is probably going to be closer to the truth with the shear not really easing till the end of the week.

Derek, I agree of the GFS. I typically use the Rule of Thumb that if in someone's forecast logic, they use the term "but the GFS is forecasting"...I deem the logic flawed and move on...

[I-wall]

How is this not a TD? I have a tough time believing that Danny was a TC, but this is not. IMO, 94L looks much better than Danny ever did.

[RL3AO]

How is this not a TD? I have a tough time believing that Danny was a TC, but this is not. IMO, 94L looks much better than Danny ever did.

Because the data shows its not a td.

[HurricaneJoe22]

It's not a TD yet because it lacks a well-defined surface circulation center as the TWO states. That's a big requirement for it to be a TD.

[HURAKAN]

How is this not a TD? I have a tough time believing that Danny was a TC, but this is not. IMO, 94L looks much better than Danny ever did.

Because the data shows its not a td.

Danny was exposed but had a well-defined LLC. That's the difference.

[cycloneye]

12z UKMET is over my head at 18.0N-66.3W.

NEW TROPICAL STORM FORECAST TO DEVELOP AFTER 12 HOURS
FORECAST POSITION AT T+ 12 : 16.0N 55.1W

VERIFYING TIME POSITION STRENGTH TENDENCY
-------------- -------- -------- --------
00UTC 01.09.2009 16.0N 55.1W WEAK
12UTC 01.09.2009 16.2N 58.2W WEAK LITTLE CHANGE
00UTC 02.09.2009 17.0N 60.3W WEAK LITTLE CHANGE
12UTC 02.09.2009 17.5N 62.3W WEAK LITTLE CHANGE
00UTC 03.09.2009 17.5N 64.3W WEAK LITTLE CHANGE
12UTC 03.09.2009 18.0N 66.3W WEAK LITTLE CHANGE
00UTC 04.09.2009 19.0N 67.9W WEAK LITTLE CHANGE
12UTC 04.09.2009 20.0N 69.2W WEAK LITTLE CHANGE
00UTC 05.09.2009 20.5N 71.3W WEAK LITTLE CHANGE
12UTC 05.09.2009 BELOW TROPICAL STORM STRENGTH

[Derek Ortt]

Luis, it is as a very weak system

[Gustywind]

000
AXNT20 KNHC 311801
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT MON AUG 31 2009

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...SPECIAL FEATURES...

A BROAD AREA OF LOW PRESSURE ASSOCIATED WITH A 1008 MB LOW IS
CENTERED NEAR 15N52W. MAXIMUM VALUES OF LOW-LEVEL VORTICITY AND
TOTAL PRECIPITABLE WATER ARE OBSERVED IN THE VICINITY OF THE LOW
BASED ON CIMSS WAVETRAK MODEL GUIDANCE AND TPW IMAGERY. THE
ASSOCIATED CONVECTION IS BEING ENHANCED AND MAINTAINED BY AN
UPPER LEVEL RIDGE ALONG 17N THAT IS PROVIDING UPPER LEVEL
DIVERGENCE AND A FAVORABLE ENVIRONMENT TO THE NW OF THE LOW
CENTER. SCATTERED/NUMEROUS STRONG CONVECTION IS FROM 13N-17N
BETWEEN 49W-53W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG
CONVECTION ARE ELSEWHERE FROM 13N-16N BETWEEN 54W-58W AND FROM
17N-20N BETWEEN 48W-52W. THIS SYSTEM HAS THE POTENTIAL TO BECOME
A TROPICAL DEPRESSION DURING THE NEXT DAY OR SO AS IT MOVES WNW
NEAR 12 KT. INTERESTS IN THE LESSER ANTILLES SHOULD MONITOR
THE PROGRESS OF THIS SYSTEM.

[HURAKAN]

94L just reported that it's asking permission to turn back due to the approaching shear!!! j/k

Like I said last night before going to sleep, we need to wait until the storm develops to talk about all your scenarios. Here we're waiting for the storm to develop and the future looks grim. I think everyone noticed the change in the wording of the TWO, at 2 AM it said "CONDITIONS STILL APPEAR FAVORABLE FOR FURTHER DEVELOPMENT," now it says, "CONDITIONS ARE MARGINALLY FAVORABLE FOR THIS SYSTEM TO BECOME A TROPICAL DEPRESSION."

[cycloneye]

18 UTC Best Track

AL, 94, 2009083118, , BEST, 0, 156N, 534W, 25, 1008, DB

[Frank2]

SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A BROAD AREA OF LOW
PRESSURE LOCATED ABOUT 500 MILES EAST OF THE LESSER ANTILLES
CONTINUE TO SHOW SIGNS OF ORGANIZATION...HOWEVER THERE IS NO
WELL-DEFINED SURFACE CIRCULATION CENTER....

Far out - glad I held to the "no circulation seen (at least at the surface)" thinking...

[Derek Ortt]

not really sure why they are saying marginally favorable. There is not much favorable about the current environment

[Evil Jeremy]

The ULL is moving faster to the west than 94L is, which will only increase the shear. It already looks like the convection is hitting a wall: http://www.ssd.noaa.gov/goes/east/carb/loop-wv.html

[Gustywind]

DATE/TIME LAT LON CLASSIFICATION STORM
31/1745 UTC 15.5N 53.6W T1.5/1.5 94L
31/1145 UTC 15.2N 51.5W T1.5/1.5 94L
31/0615 UTC 14.1N 49.5W T1.0/1.5 94L
http://www.ssd.noaa.gov/PS/TROP/tdpositions.html


Latest from NRL:
20090831.1745.94LINVEST.25kts-1008mb-150N-521W.
http://www.nrlmry.navy.mil/tc-bin/tc_ho ... m&PROD=vis

[cycloneye]

Luis, it is as a very weak system

I know is not a hurricane,but we haved experienced tragedys with massive floods by Tropical wave (1985) Invest 97L in mid July 2009 and more.

[Derek Ortt]

for those that want to see a well developed system, and some D and D, follow Jimena

[cycloneye]

WHXX01 KWBC 311824
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1824 UTC MON AUG 31 2009

DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.
PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE
AND SUBTROPICAL CYCLONE INFORMATION.

ATLANTIC OBJECTIVE AIDS FOR

DISTURBANCE INVEST (AL942009) 20090831 1800 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
090831 1800 090901 0600 090901 1800 090902 0600

LAT LON LAT LON LAT LON LAT LON
BAMS 15.6N 53.4W 16.6N 55.7W 17.8N 57.7W 18.2N 59.3W
BAMD 15.6N 53.4W 16.9N 55.5W 17.9N 57.0W 18.5N 58.3W
BAMM 15.6N 53.4W 16.4N 55.5W 17.3N 57.1W 17.6N 58.3W
LBAR 15.6N 53.4W 16.7N 55.4W 17.6N 57.2W 18.1N 59.1W
SHIP 25KTS 28KTS 35KTS 43KTS
DSHP 25KTS 28KTS 35KTS 43KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
090902 1800 090903 1800 090904 1800 090905 1800

LAT LON LAT LON LAT LON LAT LON
BAMS 18.9N 61.0W 19.9N 64.1W 20.9N 67.5W 21.6N 71.6W
BAMD 18.9N 59.4W 19.0N 61.5W 19.2N 63.8W 18.9N 66.5W
BAMM 17.8N 59.5W 17.9N 61.8W 18.1N 64.3W 18.1N 67.6W
LBAR 18.5N 61.1W 18.9N 64.7W 19.9N 67.9W 20.0N 70.1W
SHIP 55KTS 70KTS 78KTS 81KTS
DSHP 55KTS 70KTS 78KTS 73KTS

...INITIAL CONDITIONS...
LATCUR = 15.6N LONCUR = 53.4W DIRCUR = 300DEG SPDCUR = 13KT
LATM12 = 14.3N LONM12 = 50.9W DIRM12 = 305DEG SPDM12 = 13KT
LATM24 = 12.7N LONM24 = 48.6W
WNDCUR = 25KT RMAXWD = 60NM WNDM12 = 25KT
CENPRS = 1008MB OUTPRS = 1010MB OUTRAD = 180NM SDEPTH = M
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM

[HURAKAN]

[cycloneye]

12z HWRF is close for confort for northern Leewards.

http://moe.met.fsu.edu/cgi-bin/hwrftc2. ... =Animation