000
AXNT20 KNHC 051802
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST WED DEC 05 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1715 UTC.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS ACROSS W AFRICA INTO THE FAR E 
TROPICAL ATLC NEAR 8N13W WHERE THE ITCZ BEGINS AND CONTINUES 
ALONG 6N20W 7N40W 8N50W TO SOUTH AMERICA NEAR 8N60W. 
MODERATE TO ISOLATED STRONG CONVECTION IS FROM 2N-8N BETWEEN 
12W-36W. SCATTERED MODERATE TO STRONG CONVECTION FROM 3N TO 7N
BETWEEN 15W AND 32W.  

...DISCUSSION...

GULF OF MEXICO...
AN UPPER LEVEL TROUGH IS OVER THE GULF W OF 87W EXTENDING FROM 
28N93W TO NEAR 22N93W. THIS TROUGH IS SUPPORTING A COLD FRONT 
THAT EXTENDS ACROSS SW LOUISIANA ALONG 28N95W TO SOUTHERN TEXAS 
NEAR 26N97W AND THEN INTO NW MEXICO NEAR 25N98W. A SURFACE 1018 
MB LOW WITH AN EMBEDDED PRE-FRONTAL TROUGH IS PRODUCING SHOWERS 
IN SOUTHERN LOUISIANA E OF 92W. SHOWERS ARE ALSO OVER CENTRAL 
AND SOUTHERN MISSISSIPPI ASSOCIATED WITH A COLD FRONT THAT 
PASSES TROUGH SOUTHERN MISSISSIPPI...SOUTHERN LOUISIANA...THE 
TEXAS GULF COAST TO THE DEEP S OF TEXAS. A SQUALL LINE WITH 
MODERATE CONVECTION IS SW IN THE GULF FROM 22N-26N BETWEEN 
92W-97W. AN UPPER RIDGE EXTENDS ALONG 81W FROM THE STRAITS OF 
FLORIDA TO 32N COVERING THE FAR E GULF. ISOLATED SHOWERS ARE 
OVER THE SE GULF FROM 23N-26N E OF 83W ACROSS S FLORIDA AND 
THROUGH THE STRAITS OF FLORIDA. IN 24 HOURS THE SURFACE LOW IS 
EXPECTED TO REMAIN OVER THE N CENTRAL GULF PRODUCING SHOWERS. 

CARIBBEAN SEA... 

A BROAD UPPER RIDGE IN THE TROPICAL ATLC WITH AXIS ALONG THE N 
COAST OF SOUTH AMERICA TO OVER COSTA RICA IS GIVING THE 
CARIBBEAN MAINLY SW TO W FLOW ALOFT. MODERATE TO STRONG 
SUBSIDENCE WITH DRY STABLE AIR ALOFT CONTINUES TO DOMINATE MOST 
OF THE CARIBBEAN. SCATTERED SHOWERS ASSOCIATED WITH A SHEAR LINE 
CAN BE EXPECTED FROM 14N-16N BETWEEN 60W-72W. LIGHT TO MODERATE 
NE TO E TRADE WINDS ACROSS THE CARIBBEAN CONTINUE TO BANK 
SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ALONG THE 
COAST OF E HONDURAS...PANAMA AND COSTA RICA. THIS PATTERN OF 
WIND AND PRECIPITATION IS EXPECTED TO CONTINUE FOR THE NEXT
24 HOURS. CLEAR SKIES COVER THE REMAINDER OF THE CARIBBEAN SEA.

ATLANTIC OCEAN...
A 1024 MB SURFACE HIGH IN THE W ATLC NEAR 32N71W IS DISSIPATING. 
A WEST-WARD MOVING SURFACE TROUGH IS ALONG 29N73W 24N75W. IT IS
TO THE EAST OF THE BAHAMA ISLANDS. RAINSHOWERS ARE POSSIBLE WITH
THE CONTINUED MOVEMENT OF THIS FEATURE. AN UPPER TROUGH EXTENDS 
INTO THE CENTRAL ATLC THROUGH 31N51W TO 25N51W SUPPORTING
A SURFACE TROUGH THAT EXTENDS FROM 30N37W ALONG 28N43W THROUGH
A 1011 MB LOW NEAR 27N45W TO 18N49W. AN UPPER RIDGE IS TO THE
EAST EXTENDING FROM 20N48W TO BEYOND 32N32W PROVIDING 
DIFFLUENCE ALOFT TO GENERATE DENSE CLOUD COVER WITH SCATTERED 
SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 21N TO BEYOND 
32N BETWEEN 35W-47W. A SURFACE RIDGE DOMINATES THE REMAINDER OF 
THE E ATLC N OF 14N E OF 30W ANCHORED BY A 1028 MB STATIONARY 
HIGH NEAR 33N14W.  

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

$$
NAR/MT