ATL: HELENE - Post-Tropical

[brunota2003]

Looks like the lower levels are much quicker than the upper levels, sorta the same problem Ernesto had from the looks of the BAM's suite.

Yep...I pointed that out yesterday. It would keep decapitating itself, if it developed, until it found some slower air. Today's runs had the low levels at 65W and the mid levels at 55W...a spread of 10W! Not conductive for a TC, and not something I think the shear forecasts would really pick up.

Look at the last point on BAMS and BAMM on the 18Z run. BAMM is around 63W, having just cleared the Islands...while BAMS is at 80W...or nearly clear across the Caribbean!

[Florida1118]

A SURFACE LOW PRESSURE SYSTEM ASSOCIATED WITH A TROPICAL WAVE
LOCATED ABOUT 600 MILES WEST-SOUTHWEST OF THE CAPE VERDE ISLANDS
HAS CONTINUED TO BECOME BETTER DEFINED. ALTHOUGH SHOWER ACTIVITY IS
CURRENTLY DISORGANIZED...UPPER-LEVEL WINDS COULD BECOME MORE
CONDUCIVE FOR GRADUAL DEVELOPMENT OVER THE NEXT COUPLE OF DAYS.
THIS SYSTEM HAS A MEDIUM CHANCE...30 PERCENT...OF BECOMING A
TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WESTWARD AT
10 TO 15 MPH.

[cycloneye]

00z Best Track

AL, 92, 2012080800, , BEST, 0, 119N, 329W, 25, 1009, DB

ftp://ftp.nhc.noaa.gov/atcf/tcweb/inves ... 012.invest

[northjaxpro]

92L is certainly looking a bit more robust on satellite imagery compared to this time last evening. We will see if this trend continues. This system may be just far enough south to escape the influences of the SAL, which has taken apart several CV waves this season to this point.

[cycloneye]

00z Models

Code: Select all

WHXX01 KWBC 080014
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS NATIONAL HURRICANE CENTER MIAMI FL
0014 UTC WED AUG 8 2012
 
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 (AL922012) 20120808 0000 UTC
 
        ...00 HRS...   ...12 HRS...   ...24 HRS. ..   ...36 HRS...
        120808  0000   120808  1200   120809  0000   120809  1200
 
         LAT    LON     LAT    LON     LAT    LON     LAT    LON
BAMS    11.9N  32.9W   12.4N  35.5W   12.7N  38.5W   12.7N  41.6W
BAMD    11.9N  32.9W   12.5N  35.6W   12.9N  38.1W   12.9N  40.5W
BAMM    11.9N  32.9W   12.7N  35.4W   13.2N  38.0W   13.3N  40.5W
LBAR    11.9N  32.9W   12.3N  36.3W   12.9N  39.6W   13.1N  42.9W
SHIP        25KTS          29KTS          35KTS          42KTS
DSHP        25KTS          29KTS          35KTS          42KTS
 
        ...48 HRS...   ...72 HRS...   ...96 HRS. ..   ..120 HRS...
        120810  0000   120811  0000   120812  0000   120813  0000
 
         LAT    LON     LAT    LON     LAT    LON     LAT    LON
BAMS    12.3N  45.0W   12.2N  52.6W   13.2N  61.1W   14.8N  70.2W
BAMD    12.5N  42.8W   12.0N  47.2W   12.5N  50.6W   14.1N  54.1W
BAMM    13.0N  43.0W   12.3N  48.0W   12.4N  52.0W   13.3N  55.9W
LBAR    13.2N  46.0W   13.1N  51.8W   13.6N  55.7W   15.5N  57.9W
SHIP        50KTS          63KTS          69KTS          71KTS
DSHP        50KTS          63KTS          69KTS          71KTS
 
         ...INITIAL CONDITIONS...
LATCUR =  11.9N LONCUR =  32.9W DIRCUR = 270DEG SPDCUR =  17KT
LATM12 =  11.8N LONM12 =  29.6W DIRM12 = 270DEG SPDM12 =  17KT
LATM24 =  11.7N LONM24 =  26.6W
WNDCUR =   25KT RMAXWD =   60NM WNDM12 =   25KT
CENPRS = 1009MB OUTPRS = 1011MB OUTRAD =  150NM SDEPTH =   S
RD34NE =    0NM RD34SE =    0NM RD34SW =    0NM RD34NW =   0NM
 


[TropicalAnalystwx13]

Gaining a nice moisture envelope to shield it from the effects of dry air/SAL.

Don't really see why this won't develop.

[Gustywind]

Up to 30%

000
ABNT20 KNHC 072358
TWOAT

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT TUE AUG 7 2012

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...


A SURFACE LOW PRESSURE SYSTEM ASSOCIATED WITH A TROPICAL WAVE
LOCATED ABOUT 600 MILES WEST-SOUTHWEST OF THE CAPE VERDE ISLANDS
HAS CONTINUED TO BECOME BETTER DEFINED. ALTHOUGH SHOWER ACTIVITY IS
CURRENTLY DISORGANIZED...UPPER-LEVEL WINDS COULD BECOME MORE
CONDUCIVE FOR GRADUAL DEVELOPMENT OVER THE NEXT COUPLE OF DAYS.
THIS SYSTEM HAS A MEDIUM CHANCE...30 PERCENT...OF BECOMING A
TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WESTWARD AT
10 TO 15 MPH.
$$
FORECASTER STEWART/CANGIALOSI

[Gustywind]

Interresting to note that it is mentionned as a special feature... see below

000
AXNT20 KNHC 080002
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT TUE AUG 07 2012

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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL
ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2245 UTC.

...SPECIAL FEATURE...

TROPICAL WAVE IS ALONG 18N30W TO A 1012 MB SURFACE LOW AT 12N31W
MOVING W AT 15-20 KT. LOW-LEVEL CYCLONIC FLOW IS AROUND THE LOW
CENTER AND SOUTHERN PORTION OF THE WAVE. SCATTERED
MODERATE/ISOLATED STRONG CONVECTION IS MAINLY W OF THE AXIS FROM
10N-15N BETWEEN 31W-35W. WHILE THE LOW IS NOT WELL ORGANIZED AT
THIS TIME...UPPER LEVEL CONDITIONS COULD BECOME MORE CONDUCIVE
FOR FURTHER DEVELOPMENT OF THE SYSTEM OVER THE NEXT COUPLE OF
DAYS.

[Gustywind]

07/2345 UTC 12.6N 33.5W TOO WEAK 92L
07/1800 UTC 12.3N 31.3W TOO WEAK 92L

[Gustywind]

new intensity forecast out....LGEM and SHIPS brings this to a cat 1 east of windard islands.....uh Luis / Gusty you might want to be watching this one REAL close...

Thanks to you. We continue to keep an eye on it but let's wait and see the next runs to have a small idea of what could happen with 92L during the next couple of days.

[floridasun78]

i see their shear eastern carribbean that could kill it if dont move out

[Dean4Storms]

18z GFS Ensembles......

http://raleighwx.americanwx.com/models/ ... nvest2.gif

[ROCK]

I foresee this thread moving to the top of the list as early as tomorrow. Though I didnt have any tingling feeling with "E" this one however has got my attention....

[Sambucol]

I foresee this thread moving to the top of the list as early as tomorrow. Though I didnt have any tingling feeling with "E" this one however has got my attention....

Me, too.

[floridasun78]

some models make make this hurr by weekend what i hear as near leewards but shear near leedwards

[ROCK]

18Z NOGAPS...

https://www.fnmoc.navy.mil/wxmap_cgi/cg ... t=Tropical

[ROCK]

0Z GFS shows are little friend heading into the islands almost exactly the same track as Ernie.....at 111hr....keeps it weak though

http://mag.ncep.noaa.gov/NCOMAGWEB/appc ... mageSize=M

[ROCK]

by the time 92L gets in the carib Ernesto is finally moving inland? that doesnt seem right....thats 138hrs from now!

http://raleighwx.americanwx.com/models/ ... SLP138.gif

[Hurricane Alexis]

A SURFACE LOW PRESSURE SYSTEM ASSOCIATED WITH A TROPICAL WAVE
LOCATED ABOUT 700 MILES WEST-SOUTHWEST OF THE CAPE VERDE ISLANDS
HAS CHANGED LITTLE IN ORGANIZATION. ENVIRONMENTAL CONDITIONS ARE
MARGINALLY CONDUCIVE FOR GRADUAL DEVELOPMENT OVER THE NEXT COUPLE
OF DAYS. THIS SYSTEM HAS A MEDIUM CHANCE...30 PERCENT...OF BECOMING
A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WESTWARD AT
10 TO 15 MPH.

[abajan]

some models make make this hurr by weekend what i hear as near leewards but shear near leedwards

Well, quite to the contrary, our local Met stated yesterday evening that it's expected to dissipate well before reaching this region.

We shall see