000
AXNT20 KNHC 110604
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT THU OCT 11 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0515 UTC.

...SPECIAL FEATURE...

TROPICAL WAVE IS EAST OF THE LESSER ANTILLES FROM 18N52W TO 
13N53W TO A 1008 MB SURFACE LOW AT 10N54W. THE SYSTEM IS 
EXPECTED TO MOVE W-NW AT ABOUT 10 KT. THE WAVE LIES WITHIN A 
LARGE AREA OF ENHANCED DEEP LAYER MOISTURE. THIS SYSTEM HAS A 
MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 
HOURS SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 
12N-17N BETWEEN 47W-56W. GUSTY WINDS AND HEAVY RAINFALL ARE 
POSSIBLE OVER THE LESSER ANTILLES AS THE SYSTEM MOVES CLOSER TO 
THE ISLANDS. SOME GRADUAL DEVELOPMENT OF THIS SYSTEM IS EXPECTED 
OVER THE NEXT COUPLE OF DAYS. 
 
...THE ITCZ/THE MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE COAST OF SENEGAL NEAR 14N15W 
TO 7N20W TO 4N25W. THE ITCZ EXTENDS FROM 4N25W TO 3N30W TO 
3N44W. NO DEEP CONVECTION IS ASSOCIATED WITH THE ITCZ/MONSOON 
TROUGH AT THIS TIME.

...DISCUSSION...

THE GULF OF MEXICO...
AS OF 0300 UTC...A 1025 MB HIGH IS CENTERED OVER W KENTUCKY AT 
37N87W. 10-15 KT EASTERLY SURFACE WINDS ARE OVER THE GULF OF 
MEXICO. SCATTERED SHOWERS ARE OVER S FLORIDA...THE STRAITS OF 
FLORIDA...AND W CUBA. SIMILAR SHOWERS ARE OVER S MEXICO S OF THE 
BAY OF CAMPECHE. IN THE UPPER LEVELS...THE BASE OF A LARGE 
LONGWAVE UPPER LEVEL TROUGH IS OVER THE GULF N OF 24N WITH 
STRONG SUBSIDENCE. CONSIDERABLE UPPER LEVEL MOISTURE AND 
SCATTERED TO BROKEN HIGH CLOUD IS OVER S FLORIDA...THE STRAITS 
OF FLORIDA...AND W CUBA. EXPECT OVER THE NEXT 24 HOURS 
FOR SCATTERED SHOWERS TO PERSIST OVER THE S GULF S OF 23N.  

THE CARIBBEAN SEA...
A LAX SURFACE PRESSURE GRADIENT IS OVER THE CARIBBEAN SEA WITH 
PREDOMINATELY 10-15 KT EASTERLY WINDS. STRONGEST WINDS ARE ALONG 
THE COAST OF N COLOMBIA. WIDELY SCATTERED MODERATE CONVECTION IS 
OVER NICARAGUA...HONDURAS...BELIZE...AND THE NW CARIBBEAN FROM 
13N-20N BETWEEN 82W-90W. SCATTERED SHOWERS ARE OVER THE 
REMAINDER OF NICARAGUA AND COSTA RICA. SCATTERED MODERATE 
CONVECTION IS N OF JAMAICA...AND OVER S HAITI FROM 18N-20N 
BETWEEN 74W-78W. SCATTERED SHOWERS ARE OVER THE E CARIBBEAN E OF 
64W. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS CENTERED OVER 
THE GULF OF HONDURAS...WHILE NE UPPER LEVEL FLOW IS OVER THE E 
CARIBBEAN. EXPECT OVER THE NEXT 24 HOURS FOR SIMILAR CONVECTION 
TO BE OVER THE W CARIBBEAN AND CENTRAL AMERICA...WHILE 
ADDITIONAL CONVECTION ADVECTS INTO THE E CARIBBEAN FROM THE 
ATLANTIC. 

THE ATLANTIC OCEAN...
A 1011 MB LOW IS OVER THE W ATLANTIC NEAR 26N72W. A SURFACE 
TROUGH EXTENDS FROM 30N70W TO THE LOW TO THE S BAHAMAS AT 
22N72W. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 24N-27N 
BETWEEN 69W-72W. A LARGE 1028 MB HIGH IS OVER THE CENTRAL 
ATLANTIC NEAR 36N40W. A LARGE AREA OF AFRICAN DUST AND DRY AIR 
IS OVER THE E ATLANTIC N OF 15N E OF 38W. IN THE UPPER 
LEVELS...AN UPPER LEVEL LOW IS CENTERED OVER THE CENTRAL 
ATLANTIC NEAR 26N32W. ISOLATED MODERATE CONVECTION IS E OF THE 
CENTER FROM 25N-29N BETWEEN 26W-28W. ANOTHER UPPER LEVEL LOW IS 
CENTERED N OF THE LEEWARD ISLANDS NEAR 20N63W. ISOLATED MODERATE 
CONVECTION IS FROM 19N-22N BETWEEN 60W-63W. 

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

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FORMOSA