000
AXNT20 KNHC 310000
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
705 PM EST THU DEC 30 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2315 UTC.

...THE ITCZ...

THE ITCZ AXIS IS ANALYZED FROM THE COAST OF SIERRA LEONE NEAR 
7N13W WESTWARD ALONG 5N20W 4N30W 3N40W 3N50W. CLUSTERS OF 
SCATTERED MODERATE CONVECTION ARE FROM THE EQUATOR TO 5N E OF 
17W.

...DISCUSSION...

THE GULF OF MEXICO...

WATER VAPOR IMAGERY INDICATES SW FLOW ALOFT ACROSS THE BASIN 
WITH DRY AIR COVERING THE WESTERN AND NORTHERN PART OF THE GULF. 
THIS IS SUPPORTING FAIR WEATHER CONDITIONS. FOR THE CENTER AND 
EASTERN SIDE OF THE GULF ... IR IMAGERY SHOWS SOME SCATTERED 
SHOWERS AND ISOLATED THUNDERSTORMS BEING SUPPORTED BY UPPER 
LEVEL MOISTURE. SURFACE OBSERVATIONS INDICATE SOUTHEASTERLY 
WINDS OF 15-25 KT THE HALF WESTERN PART OF THE BASIN W OF 90W.   
SURFACE RIDGE REMAINS IN CONTROL OF THE EASTERN HALF OF THE GULF 
E OF 90W...INFLUENCED BY A 1022 MB HIGH OVER THE WEST 
ATLANTIC...PROVIDING A WARMER 15-20 KT SE FLOW ACROSS THE AREA.  
IT IS EXPECTED THAT FOR THE WEEKEND A COLD FRONT WILL BE 
ENTERING THE NW GULF FRI AFTERNOON...ALONG WITH LOW LEVEL 
MOISTURE FROM THE NW CARIBBEAN ADVECTING NORTHWARD ACROSS THE 
CENTRAL GULF.

THE CARIBBEAN SEA...

BROAD SURFACE ANTICYCLONIC WIND FLOW COVERS THE AREA THAT IS TO 
THE NORTH OF 18N BETWEEN 60W AND 85W...MOSTLY ACROSS THE GREATER 
ANTILLES. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND POSSIBLE 
PRECIPITATION  ARE ASSOCIATED WITH A REMNANT CLOUD LINE FROM
THE LAST COLD FRONT...WITHIN 60 NM ON EITHER SIDE OF THE LINE 
THAT PASSES THROUGH 18N60W 16N70W TO EASTERN COASTAL HONDURAS.
CONVECTIVE DEBRIS CLOUDS FROM EARLIER PRECIPITATION COVER PANAMA 
AND COSTA RICA BETWEEN 80W AND 84W. THIS PRECIPITATION WAS 
OCCURRING IN THE AREA OF A SURFACE TO LOW LEVEL TROUGH THAT HAS 
BEEN EMANATING FROM AN EASTERN PACIFIC OCEAN 1008 MB LOW 
PRESSURE CENTER THAT IS NEAR 5N78W.
  
THE ATLANTIC OCEAN...

A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 34N55W TO 
27N58W. THIS TROUGH SUPPORTS THE COLD FRONT THAT PASSES THROUGH
32N56W TO 32N67W...BECOMING STATIONARY AND CONTINUING ALONG 32N
TO THE GEORGIA COASTAL WATERS. A MIDDLE LEVEL TO UPPER LEVEL 
SHORTWAVE TROUGH PASSES THROUGH 33N74W TO 28N78W. NO DEEP 
CONVECTIVE PRECIPITATION IS APPARENT IN SATELLITE IMAGERY.
AN EASTERN ATLANTIC OCEAN MIDDLE LEVEL TO UPPER LEVEL TROUGH
SUPPORTS THE COLD FRONT THAT PASSES THROUGH 32N31W TO 27N40W
AND 22N46W...BECOMING STATIONARY AND CONTINUING TO ANTIGUA IN 
THE NORTHEASTERN CARIBBEAN SEA. BROKEN TO OVERCAST MULTILAYERED 
CLOUDS AND ISOLATED MODERATE RAINSHOWERS ARE WITHIN 60 NM TO
120 NM ON EITHER SIDE OF THE LINE THAT PASSES THROUGH 32N30W
TO 24N40W 21N50W BEYOND 18N60W. THE REMNANT CLOUD LINE THAT 
CONTINUES INTO THE CARIBBEAN SEA SIMPLY IS THE EXTENSION
OF THE CLOUDINESS THAT IS ASSOCIATED WITH THE FRONTAL BOUNDARY.
A SURFACE RIDGE EXTENDS FROM A 1022 MB HIGH PRESSURE CENTER THAT 
IS NEAR 27N73W TO 23N56W. SURFACE ANTICYCLONIC WIND FLOW COVERS 
THE AREA TO THE NORTH OF 18N BETWEEN AFRICA AND THE COLD 
FRONT...MOVING AROUND A 1016 MB HIGH PRESSURE CENTER THAT IS 
NEAR 26N24W.

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

$$

RAMOS/MT