000
AXNT20 KNHC 141740
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 PM EST TUE DEC 14 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 
1730 UTC.

...ITCZ...
 
THE ITCZ AXIS IS ANALYZED FROM THE COAST OF GUINEA NEAR 9N13W 
EXTENDING WESTWARD ALONG 10N24W 8N35W 5N44W 2N51W. ISOLATED 
MODERATE CONVECTION IS OFF THE COAST OF LIBERIA FROM 3N TO 6N 
BETWEEN 12W AND 15W. WIDELY SCATTERED MODERATE CONVECTION IS 
FROM 4N TO 11N BETWEEN 21W AND 31W. SIMILAR CONVECTION IS WITHIN 
60 NM EITHER SIDE OF THE AXIS BETWEEN 34W AND 47W.

...DISCUSSION...

GULF OF MEXICO...
WATER VAPOR IMAGERY CONTINUES TO SHOW STRONG SUBSIDENCE AND DRY 
STABLE AIR ALOFT DOMINATING THE GULF WATERS THIS AFTERNOON. AT 
SURFACE...ANTI-CYCLONIC FLOW OF 10-15 KT IS OBSERVED ACROSS THE 
REGION WITH LOW LEVEL STRATOCUMULUS CLOUDS MOVING ALONG WITH 
THIS FLOW. AN UPPER LEVEL RIDGE CONTINUES TO SLOWLY BUILD OVER 
THE GULF ANCHORED OVER THE CENTRAL PLAIN STATES AND WITH A 1024 
MB HIGH OVER E MEXICO NEAR TAMPICO...USHERING IN A VERY COOL AND 
DRY CONTINENTAL POLAR AIRMASS TO THE BASIN. THIS COOL DRY AIR 
WILL REMAIN OVER THE GULF FOR THE NEXT 24 HOURS AS S RETURN FLOW 
INCREASES TO 20-25 KT OVER THE NW GULF BY WEDNESDAY AFTERNOON.

CARIBBEAN SEA...
A STATIONARY FRONT ENTERS THE CARIBBEAN FROM THE W ATLC ACROSS 
HISPANIOLA NEAR 19N70W TO 15N74W...BECOMING A SHEAR AXIS TO THE 
COAST OF COLOMBIA NEAR 9N76W. SCATTERED SHOWERS ARE WITHIN 70 NM 
ON EITHER SIDE OF THE FRONT AND SHEAR AXIS...INCLUDING OVER 
HISPANIOLA AND THE MONA PASSAGE. BROKEN TO OVERCAST COLD AIR 
STRATOCUMULUS CLOUDS ARE OVER THE REMAINDER OF THE NW CARIBBEAN 
W OF THE BOUNDARY. ZONAL FLOW ALOFT COVERS THE NW CARIBBEAN WITH 
STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT THUS LIMITING ANY 
DEEP SHOWER ACTIVITY IN THIS REGION. A BROAD UPPER RIDGE 
ANCHORED IN THE W TROPICAL ATLC IS INFLUENCING THE REMAINDER OF 
THE CARIBBEAN DRAWING TROPICAL MOISTURE N OVER THE CENTRAL 
CARIBBEAN TO ACROSS HISPANIOLA AND PUERTO RICO. THE E CARIBBEAN 
IS UNDER MODERATE/STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT 
GIVING THE AREA FAIR WEATHER THIS AFTERNOON.  

ATLANTIC OCEAN...
A DEEP LAYERED TROUGH IS OVER THE NW ATLANTIC WITH TROUGHING 
DIPPING SOUTH TO W ATLC WATERS. WATER VAPOR IMAGERY INDICATES 
THAT MOSTLY DRY AIR AND W-SW FLOW ALOFT DOMINATES W OF 58W. THIS 
TROUGHING SUPPORTS A COLD FRONT THAT ENTERS THE DISCUSSION AREA 
NEAR 32N59W AND EXTENDS SW ALONG 26N62W 21N67W BECOMING STNRY TO 
HISPANIOLA NEAR 19N70W. LOW-LEVEL CONVERGENCE EAST OF THE FRONT 
IS GENERATING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS 
WITHIN 180 NM EAST OF THE FRONT. BROKEN TO OVERCAST COLD AIR 
STRATOCUMULUS CLOUDS ARE OVER THE REMAINDER OF THE W ATLC W OF 
THE FRONT. SURFACE RIDGING EXTENDS ACROSS THE CENTRAL ATLC 
PROVIDING OVERALL FAIR WEATHER CONDITIONS BETWEEN 35W AND 53W. 
AN UPPER LEVEL TROUGH CONTINUES TO MOVE ACROSS THE EASTERN ATLC 
SUPPORTING A 1001 MB SURFACE LOW CENTERED NEAR 34N27W. A COLD 
FRONT EXTENDS SW FROM THE LOW CENTER ALONG 26N28W TO 22N33W WITH 
SCATTERED SHOWERS OCCURRING WITHIN 80 NM EAST OF THE FRONT. 
ISOLATED SHOWERS ARE BEHIND THE FRONT N OF 25N IN ASSOCIATION 
WITH THE UPPER LEVEL TROUGHING.

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

$$

GARCIA