000
AXNT20 KNHC 120000
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
705 PM EST MON JAN 11 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 2345 UTC.

...THE ITCZ...

THE ITCZ AXIS IS ANALYZED FROM WEST AFRICA NEAR THE NORTHERN 
COAST OF LIBERIA AT 6N11W CONTINUING WESTWARD ALONG 5N20W 3N30W 
2N40W TO NORTHEAST BRAZIL NEAR THE CITY OF MACAPA AT EQ. 
WEAK CONVECTION IS FOUND ALONG THE ITCZ BETWEEN 30W AND 35W. 
SIMILAR CONVECTION IS FOUND FROM 3N TO 5N BETWEEN 14W AND 16W.

...DISCUSSION...

THE GULF OF MEXICO...
WEAK SURFACE PRESSURE GRADIENT IS SEEN ACROSS THE GULF OF MEXICO 
AS A 1032 MB HIGH PRESSURE MOVES OVER THE NORTHERN BASIN NEAR 
28N80W...BRINGING A COLD AND DRY AIRMASS TO THE REGION. SHIP AND 
OIL PLATFORM OBSERVATIONS SHOW 5 TO 15 KT ANTI-CYCLONIC FLOW 
OVER THE ENTIRE BASIN. SATELLITE VISIBLE IMAGERY AND DOPPLER 
RADAR DATA SHOW A WEAK LINE OF SHOWERS ALONG THE MEXICO COAST 
FROM NORTH OF VERACRUZ TO MATAMOROS. SATELLITE WATER VAPOR 
IMAGERY SHOWS UPPER LEVEL MOISTURE ENTERING THE SOUTHWEST CORNER 
OF THE BASIN. THIS UPPER LEVEL MOISTURE IS BEEN TRANSFERRED FROM 
THE EAST TROPICAL PACIFIC INTO THE BASIN. THE WEATHER ACROSS THE 
GULF WILL CONTINUE TO BE DOMINATED BY THE HIGH PRESSURE SYSTEM 
OVER THE NEXT 24 HOURS. THEREFORE...NO SIGNIFICANT CHANGES ARE 
EXPECTED DURING THIS TIME PERIOD.

THE CARIBBEAN SEA...
A STATIONARY FRONT ENTERS THE CARIBBEAN SEA FROM THE WESTERN 
ATLANTIC THROUGH THE MONA PASSAGE AND CONTINUES WEST-SOUTHWEST 
ALONG 18N70W 16N75W 13N80W TO THE SOUTHWEST BASIN NEAR SOUTHERN 
COSTA RICA AT 10N82W. INFRA-RED SATELLITE IMAGERY SHOWS WEAK 
CONVECTION WITHIN 60 NM ON EITHER SIDE OF THE STATIONARY FRONT. 
THIS FRONT CONTINUES TO GENERATE A TIGHT SURFACE PRESSURE 
GRADIENT WITHIN 150 NM OFF THE COAST OF NICARAGUA...COSTA 
RICA...AND PANAMA. THEREFORE...NORTHERLY GALE WINDS ARE OBSERVED 
IN THIS REGION. CONDITIONS ARE EXPECTED TO DECREASE TO BELOW 
GALE FORCE CRITERIA OVER THE NEXT 6 TO 12 HOURS. SHIP AND BUOY 
OBSERVATIONS SHOW NORTH-NORTHEAST WINDS 10 TO 20 KT OVER THE 
NORTHWEST BASIN. ELSEWHERE EAST OF THE FRONTAL BOUNDARY...FAIR 
WEATHER CONTINUES WITH MODERATE TO FRESH TRADE WINDS...AS AN 
UPPER LEVEL RIDGE OF HIGH PRESSURE PROVIDES STRONG SUBSIDENCE 
AND DRY AIR TO THE MID AND UPPER LEVELS ACROSS THIS REGION. 

THE ATLANTIC OCEAN...
A SURFACE LOW PRESSURE SYSTEM IS OVER THE WESTERN ATLANTIC NEAR 
33N58W. A COLD FRONT EXTENDS SOUTH-SOUTHWEST FROM THE LOW CENTER 
AND ENTERS THE DISCUSSION AREA NEAR 30N60W...AND CONTINUES ALONG 
26N61W 22N64W ENTERING THE CARIBBEAN SEA THROUGH THE MONA 
PASSAGE. THIS FRONT IS MOVING ALONG WITH AN UPPER LEVEL TROUGH 
THAT IS SUPPORTING THE LOW PRESSURE SYSTEM. GALE FORCE WINDS ARE 
OBSERVED WEST OF THE FRONT TO 68W AND NORTH OF 28N. INFRA-RED 
SATELLITE IMAGERY SHOWS WEAK TO MODERATE CONVECTION 120 NM ON 
EITHER SIDE OF THE FRONT NORTH OF 28N. THE REMAINDER OF THE 
ATLANTIC OCEAN IS DOMINATED BY A STRONG UPPER LEVEL RIDGE OF 
HIGH PRESSURE...BRINGING GENERALLY FAIR WEATHER CONDITIONS 
ACROSS THE REMAINDER OF THE ATLANTIC. OVER THE NEXT 24 
HOURS...THE COLD FRONT WILL EXPAND INTO THE CENTRAL ATLANTIC 
WITH CONVECTION WITHIN AND AHEAD OF IT.

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

$$

GARCIA