000
AXNT20 KNHC 191746
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 PM EST SUN DEC 19 2010

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.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 8N14W 6N24W 7N30W 5N37W 9N49W. 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS ALONG THE 
COAST OF WEST AFRICA FROM 3N-8N BETWEEN 10W-16W. CLUSTERS OF 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION ARE FROM WITHIN 
180 NM N OF THE ITCZ FROM 21W-28W AND 11N TO S OF THE EQUATOR 
BETWEEN 32W-47W. A SURFACE TROUGH IS EMBEDDED WITHIN THE ITCZ 
EXTENDING FROM 11N51W TO INLAND OVER FRENCH GUIANA WITH 
SCATTERED SHOWERS FROM 9N-11N BETWEEN 48W-50W AND POSSIBLE 
ISOLATED SHOWERS ARE WITHIN 60 NM OF THE TROUGH AXIS.    

...DISCUSSION...

GULF OF MEXICO...
AS OF 1500 UTC...A COLD FRONT EXTENDS ACROSS N CUBA JUST E OF 
HAVANA BECOMING STATIONARY N OF THE YUCATAN CHANNEL NEAR 22N85W 
INTO THE E BAY OF CAMPECHE TO S MEXICO NEAR CIUDAD DEL CARMEN. 
THIS SYSTEM IS SUPPORTED BY AN UPPER LEVEL LONGWAVE TROUGH THAT 
COVERS THE ENTIRE AREA. POSSIBLE ISOLATED SHOWERS DOT THE E GULF 
E OF 88W WITH STRONG SUBSIDENCE AND DRY STABLE AIR S OF 25N 
LIMITING ALL BUT LOW LEVEL ACTIVITY. AS OF 1500 UTC...A WEAK 
SURFACE TROUGH IS IN THE SW GULF ALONG 19N96W TO 22N97W 
PRODUCING POSSIBLE LOW LEVEL SHOWERS WITHIN 45 NM OF THE AXIS. 
THE NW GULF IS EXPERIENCING FAIR WEATHER THIS AFTERNOON. EXPECT 
THE FRONT DISSIPATE IN THE NEXT 24 HOURS.

CARIBBEAN SEA...
THE UPPER TROUGH THAT COVERS THE GULF OF MEXICO DIPS OVER THE NW 
CARIBBEAN W OF A LINE FROM CUBA NEAR THE GULF OF GUACANAYABO TO 
HONDURAS NEAR CABO CAMARON. THE REMAINDER OF THE CARIBBEAN IS 
DOMINATED BY AN UPPER RIDGE ANCHORED NEAR THE ABC ISLANDS. A 
WEAK SURFACE TROUGH CROSSES E CUBA/WINDWARD PASSAGE TO 18N75W 
GENERATING SCATTERED SHOWERS N OF 16N BETWEEN 71W AND THE 
SURFACE TROUGH. THE E CARIBBEAN HAS POCKETS OF SCATTERED SHOWERS 
WITHIN 90 NM OF A LINE FROM 14N74W TO OVER THE WINDWARD ISLANDS 
NEAR SAINT VINCENT. ISOLATED MODERATE CONVECTION IS OVER PANAMA 
AND N COLOMBIA INTO THE SW CARIBBEAN CAUSED BY THE UPPER RIDGE 
DRAWING MOISTURE N FROM THE ITCZ IN THE E PACIFIC. THE REMAINDER 
OF THE CARIBBEAN IS ENJOYING FAIR WEATHER THIS AFTERNOON.

ATLANTIC OCEAN...
THE UPPER TROUGH THAT COVERS THE GULF OF MEXICO AND INTO THE NW 
CARIBBEAN EXTENDS OVER THE W ATLC TO 72W SUPPORTING A COLD FRONT 
THAT EXTENDS FROM 32N74W ACROSS THE N BAHAMAS AND THE STRAITS OF 
FLORIDA TO N CUBA NEAR 23N82W. A WEAK SURFACE LOW IS NEAR 26N75W 
WITH A SURFACE TROUGH EXTENDING S ACROSS THE CENTRAL BAHAMAS 
NEAR 23N74W TO E CUBA/WINDWARD PASSAGE PRODUCING SCATTERED 
SHOWERS/ISOLATED THUNDERSTORMS WITHIN 225 NM E OF THE TROUGH/LOW 
WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS N OF 
26N BETWEEN 67W AND THE COLD FRONT. A 1017 MB HIGH IS FURTHER E 
NEAR 28N58W. AN UPPER TROUGH IS IN THE CENTRAL AND E ATLC N OF 
14N BETWEEN 25W-50W SUPPORTING A WEAK COLD FRONT THAT ENTERS THE 
E ATLC NEAR 32N24W ALONG 24N31W TO 20N45W WITH ISOLATED SHOWERS 
WITHIN 45 NM EITHER SIDE OF THE FRONT. AN UPPER RIDGE IS INLAND 
OVER W AFRICA ENHANCING SCATTERED SHOWERS WITHIN 60 NM OF LINE 
FROM 26N24W TO 30N18W AND N OF 31N BETWEEN 14W AND THE ABOVE 
COLD FRONT. 

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

$$
SMM/PAW