ATL GUSTAV: Tropical Depression - Discussion

[cycloneye]

The 18:00 UTC Best Track for 94L:

AL, 94, 2008081918, , BEST, 0, 130N, 379W, 25, 1009, DB, 0, , 0, 0, 0, 0,

ftp://ftp.tpc.ncep.noaa.gov/atcf/tcweb/

[Gustywind]

After being too weak for classification,ssd dvorak gives 94L 1.0/1.0 this afternoon.

19/1745 UTC 13.0N 37.3W T1.0/1.0 94L -- Atlantic Ocean

http://www.ssd.noaa.gov/PS/TROP/positions.html

Posting in the same time, i give you a gold ex aqueo medal

You are in the Oylimpics spirit. Anyway,the system looks good this afternoon.Lets see if it persists and that is the key.

Yeah my friend Cycloneye the Olympics spirit S2K board giving quickly the infos beetween the hurdles (of shear maybe?!lol . More seriously, persistence is the key factor and we should continue to monitor this system, always seducive and afterwards suspicious in this part of the season ....

[cycloneye]

From the 94L Model Runs thread:

SHIP for the second run in a row shows light shear ahead.

Code: Select all

ATLANTIC SHIPS INTENSITY FORECAST       *
                    *        GOES/OHC INPUT INCLUDED            *
                    *      INVEST  AL942008  08/19/08  18 UTC   *

TIME (HR)          0     6    12    18    24    36    48    60    72    84    96   108   120
V (KT) NO LAND    25    28    31    35    38    45    52    59    64    67    72    75    78
V (KT) LAND       25    28    31    35    38    45    52    59    64    67    72    75    78
V (KT) LGE mod    25    26    27    28    30    34    39    44    50    56    64    71    78

SHEAR (KTS)        8    10     8     6     8    11     8     9     6     9     3     7     5

[Hurricaneman]

maybe its a case of the ULL is getting ahead of the Invest

[GCANE]

Its looking better than this morning.

[ROCK]

0z GFS run should be interesting tonight. Seems a rather large ridge set-up as Dr Masters suggested.

[Gustywind]

http://www.ssd.noaa.gov/goes/flt/t2/loop-ir4.html
Shear to the NW part of 94L can be seen , but convection is popping fairly abit everywhere and especially ahead and to the southwest with my untrained eyes...in spite of decents signs of rotation, should it persists to see maybe another TD during the next 48h....

[cycloneye]

The San Juan NWS office discussion says it all clear.

FXCA62 TJSJ 191823
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
223 PM AST TUE AUG 19 2008

.DISCUSSION...

THE NEXT BIG QUESTION MARK FOR THE WEATHER INTO THE FIRST HALF OF
THE WEEKEND REMAINS THE PROXIMITY OF THE FIRST OF TWO LARGE AREAS OF
CONVECTION IN THE TROPICAL ATLANTIC. EQUATORIAL AND MONSOONAL
TROUGHS ALONG THE ITCZ ARE CURRENTLY SETTING UP A MINI NURSERY IN
THE EASTERN TROPICAL ATLANTIC FACILITATING THE PRESERVATION OF NEW
WAVES EXITING OFF THE COAST OF AFRICA. OVER THE NEXT FEW
DAYS...INCREASED CONVECTION IS POSSIBLE WITH THE FIRST WAVE
/DESIGNATED AL94 CURRENTLY NEAR 40W/ ESPECIALLY IN THE OVERNIGHT
HOURS AS EVAPORATIVE COOLING EFFECTS TAKE OVER NEAR CLOUD TOPS. PER
NHC GUIDANCE...UPPER-LEVEL WINDS MAY BECOME UNFAVORABLE FOR DEEP
TROPICAL DEVELOPMENT IF THE WAVE MOVES MORE TO THE NORTHWEST WITH
TIME. IF HOWEVER THE SYSTEM TAKES A MORE SOUTHERLY TRACK OF THE
UPPER LOW...IT COULD ENCOUNTER A MORE FAVORABLE UPPER-LEVEL WIND
PATTERN. THAT...COUPLED WITH CLIMATOLOGY /MID-TO-LATE AUGUST/ AND
WARM SSTS...GIVES THIS WAVE A BETTER CHANCE FOR TROPICAL
DEVELOPMENT. AT THIS TIME HOWEVER...THE MEDIUM-RANGE GFS TRACKS
THE WAVE MORE WEST NORTHWEST...PLACING THE SYSTEM IN THE PATH OF
MORE UNFAVORABLE WINDS AND KEEPING IT AS AN OPEN LOW. LATEST AL94
EARLY-CYCLE INVEST RUNS SHOW AN ENSEMBLE MEAN TRACK TAKING THE
SYSTEM JUST TO THE NORTHEAST OF THE FORECAST AREA VERY NEAR THE
NORTHERN LEEWARD ISLANDS...HOWEVER THIS FORECAST IS WELL INTO THE
FUTURE AND DEPENDING ON WHERE THE MODEL INITIALIZED ITS CENTER
POSITION...WE WILL PROBABLY SEE FUTURE TRACK CHANGES WITH TIME.

GIVEN THIS UNCERTAINTY...STAY TUNED TO YOUR NATIONAL WEATHER
SERVICE FOR THE LATEST INFORMATION.

http://www.srh.noaa.gov/fwd/productview ... &version=0

[Gustywind]

The San Juan NWS office discussion says it all clear.

FXCA62 TJSJ 191823
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
223 PM AST TUE AUG 19 2008

.DISCUSSION...

THE NEXT BIG QUESTION MARK FOR THE WEATHER INTO THE FIRST HALF OF
THE WEEKEND REMAINS THE PROXIMITY OF THE FIRST OF TWO LARGE AREAS OF
CONVECTION IN THE TROPICAL ATLANTIC. EQUATORIAL AND MONSOONAL
TROUGHS ALONG THE ITCZ ARE CURRENTLY SETTING UP A MINI NURSERY IN
THE EASTERN TROPICAL ATLANTIC FACILITATING THE PRESERVATION OF NEW
WAVES EXITING OFF THE COAST OF AFRICA. OVER THE NEXT FEW
DAYS...INCREASED CONVECTION IS POSSIBLE WITH THE FIRST WAVE
/DESIGNATED AL94 CURRENTLY NEAR 40W/ ESPECIALLY IN THE OVERNIGHT
HOURS AS EVAPORATIVE COOLING EFFECTS TAKE OVER NEAR CLOUD TOPS. PER
NHC GUIDANCE...UPPER-LEVEL WINDS MAY BECOME UNFAVORABLE FOR DEEP
TROPICAL DEVELOPMENT IF THE WAVE MOVES MORE TO THE NORTHWEST WITH
TIME. IF HOWEVER THE SYSTEM TAKES A MORE SOUTHERLY TRACK OF THE
UPPER LOW...IT COULD ENCOUNTER A MORE FAVORABLE UPPER-LEVEL WIND
PATTERN. THAT...COUPLED WITH CLIMATOLOGY /MID-TO-LATE AUGUST/ AND
WARM SSTS...GIVES THIS WAVE A BETTER CHANCE FOR TROPICAL
DEVELOPMENT. AT THIS TIME HOWEVER...THE MEDIUM-RANGE GFS TRACKS
THE WAVE MORE WEST NORTHWEST...PLACING THE SYSTEM IN THE PATH OF
MORE UNFAVORABLE WINDS AND KEEPING IT AS AN OPEN LOW. LATEST AL94
EARLY-CYCLE INVEST RUNS SHOW AN ENSEMBLE MEAN TRACK TAKING THE
SYSTEM JUST TO THE NORTHEAST OF THE FORECAST AREA VERY NEAR THE
NORTHERN LEEWARD ISLANDS...HOWEVER THIS FORECAST IS WELL INTO THE
FUTURE AND DEPENDING ON WHERE THE MODEL INITIALIZED ITS CENTER
POSITION...WE WILL PROBABLY SEE FUTURE TRACK CHANGES WITH TIME.

GIVEN THIS UNCERTAINTY...STAY TUNED TO YOUR NATIONAL WEATHER
SERVICE FOR THE LATEST INFORMATION.

http://www.srh.noaa.gov/fwd/productview ... &version=0

Very interresting Cycloneye, seems that something is cooking

[ROCK]

You island guys need to look at the latest EURO......not good for you. Hopefully it will be a weak system.

[Gustywind]

You island guys need to look at the latest EURO......not good for you. Hopefully it will be a weak system.

Tkanks ROCK and could you provide me the link of the EURO please?

[cycloneye]

Its flaring.

[HURAKAN]

Trying even during DMIN!!!

[alienstorm]

Its flaring.

Thunderstorms building on or near apparent center of circulation.

[cycloneye]

Lets watch the 8 PM TWO and see if NHC upgrades to code red.

[KWT]

Well its been flaring convection now for at least the last 36hrs and its got a pretty good low that must be nearly closed, no reason why this should be code red to be honest.

[HURAKAN]

Conditions at 41026 as of
2000 GMT on 08/19/2008:

Code: Select all

 Air Temperature (ATMP): 80.4 °F
 Water Temperature (WTMP): 82.9 °F
 Wind Speed (WSPD): 9.9 kts
 Wind Direction (WDIR): SW (220 deg)

LLC now to the NW of this buoy.

[msbee]

The San Juan NWS office discussion says it all clear.

FXCA62 TJSJ 191823
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
223 PM AST TUE AUG 19 2008

.DISCUSSION...

THE NEXT BIG QUESTION MARK FOR THE WEATHER INTO THE FIRST HALF OF
THE WEEKEND REMAINS THE PROXIMITY OF THE FIRST OF TWO LARGE AREAS OF
CONVECTION IN THE TROPICAL ATLANTIC. EQUATORIAL AND MONSOONAL
TROUGHS ALONG THE ITCZ ARE CURRENTLY SETTING UP A MINI NURSERY IN
THE EASTERN TROPICAL ATLANTIC FACILITATING THE PRESERVATION OF NEW
WAVES EXITING OFF THE COAST OF AFRICA. OVER THE NEXT FEW
DAYS...INCREASED CONVECTION IS POSSIBLE WITH THE FIRST WAVE
/DESIGNATED AL94 CURRENTLY NEAR 40W/ ESPECIALLY IN THE OVERNIGHT
HOURS AS EVAPORATIVE COOLING EFFECTS TAKE OVER NEAR CLOUD TOPS. PER
NHC GUIDANCE...UPPER-LEVEL WINDS MAY BECOME UNFAVORABLE FOR DEEP
TROPICAL DEVELOPMENT IF THE WAVE MOVES MORE TO THE NORTHWEST WITH
TIME. IF HOWEVER THE SYSTEM TAKES A MORE SOUTHERLY TRACK OF THE
UPPER LOW...IT COULD ENCOUNTER A MORE FAVORABLE UPPER-LEVEL WIND
PATTERN. THAT...COUPLED WITH CLIMATOLOGY /MID-TO-LATE AUGUST/ AND
WARM SSTS...GIVES THIS WAVE A BETTER CHANCE FOR TROPICAL
DEVELOPMENT. AT THIS TIME HOWEVER...THE MEDIUM-RANGE GFS TRACKS
THE WAVE MORE WEST NORTHWEST...PLACING THE SYSTEM IN THE PATH OF
MORE UNFAVORABLE WINDS AND KEEPING IT AS AN OPEN LOW. LATEST AL94
EARLY-CYCLE INVEST RUNS SHOW AN ENSEMBLE MEAN TRACK TAKING THE
SYSTEM JUST TO THE NORTHEAST OF THE FORECAST AREA VERY NEAR THE
NORTHERN LEEWARD ISLANDS...HOWEVER THIS FORECAST IS WELL INTO THE
FUTURE AND DEPENDING ON WHERE THE MODEL INITIALIZED ITS CENTER
POSITION...WE WILL PROBABLY SEE FUTURE TRACK CHANGES WITH TIME.

GIVEN THIS UNCERTAINTY...STAY TUNED TO YOUR NATIONAL WEATHER
SERVICE FOR THE LATEST INFORMATION.

http://www.srh.noaa.gov/fwd/productview ... &version=0

a mini nursery? what an interesting way of telling us things are hatching out there. LOL

[KWT]

Yeah it all hinges on this going WNW...however we all know with wave systems they tend to track to the south of the guidence until a decent strong LLC develops.

[Patrick99]

That cutoff low really dove southwest......I'm not anywhere near as bullish on this as I was.

Area directly behind 94L looks fairly robust too.