000
AXNT20 KNHC 280543
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 AM EST TUE DEC 28 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC.

...THE ITCZ...

ITCZ AXIS IS ANALYZED ALONG 6N10W 3N19W 2N34W. CLUSTERS OF 
SCATTERED MODERATE CONVECTION ARE FROM 2N-6N BETWEEN 20W-35W.   

...DISCUSSION...

GULF OF MEXICO...
SURFACE RIDGE REMAINS IN CONTROL OF THE GULF TONIGHT ANCHORED 
BY A SERIES OF 1029 MB HIGHS...ONE OVER THE MISSISSIPPI DELTA OF 
LOUISIANA...SECOND OVER W/CENTRAL MISSISSIPPI AND A THIRD OVER W 
KENTUCKY. THE BROAD UPPER TROUGH ASSOCIATED WITH THE FRONT IN 
THE W ATLC IS MOVING OUT OF THE GULF COVERING ONLY THE FAR NE 
GULF TONIGHT GIVING THE GULF NEAR ZONAL WESTERLY FLOW ALOFT WITH 
MODERATE/STRONG SUBSIDENCE AND DRY STABLE AIR. THE RETURN FLOW 
IS BANKING LOW CLOUDS WITH POSSIBLE ISOLATED SHOWERS OVER THE W 
GULF W OF 94W TO ALONG THE E SLOPES OF THE SIERRA MADRE 
MOUNTAINS OF MEXICO NE OF MINATITLAN AND INLAND OVER E TEXAS. 
THIS IS MODERATING TEMPERATURES OVER TEXAS WHILE THE 
TEMPERATURES OVER THE REMAINDER OF THE N GULF ARE HOVERING NEAR 
OR JUST BELOW FREEZING. BROKEN TO OVERCAST COLD AIR 
STRATOCUMULUS CLOUDS COVER A PORTION OF THE GULF FROM 21N-27N 
BETWEEN 84W-94W. EXPECT THE SURFACE RIDGE TO REMAIN IN CONTROL 
OF THE GULF OVER THE NEXT 24 HOURS AS IT SHIFTS SLOWLY 
EASTWARD.  

CARIBBEAN SEA...
A COLD FRONT EXTENDS FROM THE W ATLC ACROSS NW HAITI JUST E OF 
JAMAICA TO 15N80W WITH BROKEN TO OVERCAST COLD AIR STRATOCUMULUS 
CLOUDS N OF 15N W OF THE FRONT. ISOLATED SHOWERS ARE WITHIN 45 
NM E OF THE FRONT. THE ENTIRE CARIBBEAN IS UNDER SW TO W FLOW 
ALOFT IN RESPONSE TO AN UPPER RIDGE ANCHORED IN THE TROPICS. 
DIFFLUENCE ALOFT OVER THE CENTRAL CARIBBEAN COMBINED WITH THE 
STRONG N TO NE SURFACE WINDS ARE GENERATING AN AREA OF DENSE 
MULTILAYERED CLOUDS WITH SCATTERED SHOWERS S OF 15N W OF 71W TO 
INLAND OVER CENTRAL AND SOUTH AMERICA...AND N OF 15N TO OVER 
PUERTO RICO AND HISPANIOLA BETWEEN 67W-76W. THIS IS LEAVING THE 
SE CARIBBEAN EXPERIENCING FAIR WEATHER AGAIN TONIGHT. 

ATLANTIC OCEAN...
BROAD UPPER TROUGH COVERS THE W ATLC N OF 24N W OF 57W INTO THE 
FAR E GULF OF MEXICO SUPPORTING A STRONG COLD FRONT THAT ENTERS 
THE W/CENTRAL ATLC NEAR 32N58W ALONG 25N66W JUST E OF THE TURKS 
AND CAICOS ACROSS NW HAITI INTO THE CARIBBEAN. AN UPPER RIDGE 
AXIS IS JUST TO THE E EXTENDING FROM THE TROPICS NEAR 9N57W TO 
BEYOND 32N48W ENHANCING SCATTERED SHOWERS WITHIN 350/400 NM E OF 
THE ABOVE FRONT. BROKEN TO OVERCAST COLD AIR STRATOCUMULUS 
CLOUDS REMAIN W OF THE FRONT. AN UPPER LEVEL TROUGH IS IN THE E 
ATLC N OF 10N E OF 37W TO THE COAST OF W AFRICA SUPPORTING A 
COLD FRONT THAT ENTERS THE E ATLC NEAR 32N18W EXTENDING TO 
27N26W WHERE IT DISSIPATES TO 221N34W WITH ISOLATED SHOWERS 
WITHIN 60 NM E OF THE FRONT. THIS FRONT CONTINUES TO SPLIT A 
BROAD SURFACE RIDGE THAT COVERS THE REMAINDER OF THE CENTRAL AND 
E ATLC TO OVER AFRICA WITH A 1022 MB HIGH W OF THE FRONT NEAR 
30N43W AND A 1025 MB HIGH OVER ALGERIA NEAR 32N3W.  

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

$$
PAW