000
AXNT20 KNHC 280005
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
705 PM EST SUN DEC 27 2009

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...

FROM COASTAL LIBERIA NEAR 6N9W TO 4N25W TO 2N36W TO 2N45W...
INTO NORTHEASTERN BRAZIL NEAR 1N50W. SHOWERS ARE POSSIBLE
FROM 1N TO 4N BETWEEN 38W AND COASTAL BRAZIL NEAR 50W...
AND WITHIN 30 NM TO 60 NM ON EITHER SIDE OF 6N13W 5N19W
4N25W 4N27W.

...DISCUSSION...

THE GULF OF MEXICO...
THE MIDDLE LEVEL TO UPPER LEVEL ACROSS THE AREA CONTINUES TO BE 
SOUTHWESTERLY. THE BASE OF A TROUGH THAT IS MOVING THROUGH THE 
OHIO VALLEY OF THE U.S.A. STOPS JUST TO THE NORTH OF THE U.S.A. 
GULF COAST STATES. A SURFACE TROUGH EXTENDS FROM A 1014 MB LOW 
PRESSURE CENTER THAT IS NEAR 25N88W TO 21N93W. A WELL-DEFINED 
CLOUD LINE IS ASSOCIATED WITH THIS TROUGH. A SECOND SURFACE 
TROUGH IS ALONG THE MEXICO COAST FROM 19N95W NEAR THE ISTHMUS OF 
TEHUANTEPEC TO 24N98W. MULTILAYERED CLOUDS ALSO ARE AROUND THIS 
TROUGH.  

THE CARIBBEAN SEA...
A SURFACE TROUGH IS ALONG 84W/85W FROM 16N TO THE YUCATAN CHANNEL
ALONG THE WESTERN TIP OF CUBA. SHOWERS ARE POSSIBLE AROUND THE 
TROUGH. SHOWERS ALSO ARE POSSIBLE WITHIN 60 NM ON EITHER SIDE OF 
13N80W 16N80W 18N78W IN JAMAICA. SHOWERS ARE POSSIBLE FROM 18N 
TO 20N BETWEEN 60W AND PUERTO RICO...NEAR THE STATIONARY FRONT
THAT HAS BEEN IN THE ATLANTIC OCEAN FOR AT LEAST THE LAST FEW 
DAYS. BROAD MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC FLOW COVERS 
THE AREA. 

THE ATLANTIC OCEAN...
A COLD FRONT PASSES THROUGH 31N71W IN THE WESTERN ATLANTIC OCEAN 
TO 26N75W...BECOMING DISSIPATING STATIONARY FROM 26N75W ACROSS 
THE BAHAMAS TO 23N76W. UPPER LEVEL ANTICYCLONIC FLOW FROM A RIDGE
IS ON TOP OF THE AREA OF THE FRONT. LARGE SCALE UPPER LEVEL 
TROUGH ON WATER VAPOR IMAGERY PASSES THROUGH 32N42W TO 26N48W
TO 20N50W. THIS TROUGH SUPPORTS THE CURRENT COLD FRONT THAT 
PASSES THROUGH 31N26W 28N33W 23N40W 19N53W. A STATIONARY FRONT 
CONTINUES FROM 19N53W TO 19N60W TO 20N69W. STRATIFORM CLOUDS ARE 
TO THE NORTHWEST AND NORTH OF THE FRONT. HIGH CLOUDS ARE WITHIN 
300 NM TO 400 NM TO THE EAST AND SOUTHEAST OF THE LINE THAT 
PASSES THROUGH 31N31W 25N40W 21N49W. ISOLATED MODERATE SHOWERS 
FROM 17N TO 19N BETWEEN 50W AND 68W...INCLUDING IN THE 
NORTHEASTERN CARIBBEAN SEA. A REMNANT CLOUD LINE THAT IS 
ASSOCIATED WITH AN OLD FRONTAL BOUNDARY IS WITHIN 30 NM TO 60 NM 
ON EITHER SIDE OF 19N66W 22N71W 25N74W 27N73W BEYOND 30N71W. 
SHOWERS ARE WITHIN 30 NM TO 60 NM ON EITHER SIDE OF THE CLOUD 
LINE TO THE NORTH OF 25N. SURFACE HIGH PRESSURE COVERS THE AREA 
TO THE EAST OF THE FRONT...FROM 10N TO 30N BETWEEN AFRICA AND 
THE FRONT...AROUND A 30N10W 21N25W 15N40W 15N50W SURFACE RIDGE. 
A 1018 MB HIGH PRESSURE CENTER IS NEAR 25N18W. SURFACE HIGH 
PRESSURE IS TO THE WEST AND NORTHWEST OF THE 31N26W 19N53W 
20N69W FRONT...AROUND A 58W RIDGE...TO THE NORTH OF 20N.

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

$$
MT