000
AXNT20 KNHC 261748
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 PM EST SAT DEC 26 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1730 UTC.

...THE ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 5N10W 4N20W 2N30W 1N40W 1N50W. 
NO SIGNIFICANT CONVECTION IS OCCURRING ALONG OR NEAR THE ITCZ 
EXCEPT AN AREA OF MODERATE TO STRONG CONVECTION AT 2N50W MOVING 
WESTWARD ENTERING THE NORTHERN BRAZIL CITY OF AMAPA...AND AN 
AREA OF WEAK TO MODERATE CONVECTION OVER WEST AFRICA 80 NM SOUTH 
OF THE GHANA COAST.  

...DISCUSSION...

THE GULF OF MEXICO...
A SURFACE 1020 MB HIGH IS OVER THE NORTHERN GULF BRINGING SERENE 
WEATHER TO MOST OF THE GULF. SHIP AND BUOY OBS ARE SHOWING 
SURFACE ANTICYCLONIC 10 KTS TO 15 KTS WINDS ACROSS THE BASIN. IN 
THE UPPER LEVELS OF THE ATMOSPHERE...RIDGING IS PRODUCING 
SOUTHWEST FLOW BRINGING A MODERATE AMOUNT OF UPPER LEVEL 
MOISTURE ACROSS THE BASIN...DETECTED AS HIGH LEVEL CLOUDS. FOR 
THE NEXT 24 HOURS...MODELS ARE SUGGESTING A SURFACE TROUGH 
DEVELOPING OVER THE WESTERN GULF ALONG 94W WITH POSSIBLE 
CONVECTION IN THIS REGION. THE REMAINDER OF THE REGION WILL 
CONTINUE TO EXPERIENCE FAIR WEATHER OVER THE NEXT 24 HOURS.

THE CARIBBEAN SEA...
THE TAIL END OF A COLD FRONT IS OVER THE WESTERN CARIBBEAN FROM 
CENTRAL CUBA TO NEAR 18N84W. THIS FEATURE IS ONLY BRINGING WEAK 
CONVECTION...IF ANY...TO THE NORTHWEST BASIN. THE TAIL END OF 
THIS FRONT IS EXPECTED TO DISSIPATE OVER THE NEXT 24 HOURS. THE 
MAIN WEATHER PRODUCER IS A UPPER LEVEL HIGH PRESSURE SYSTEM OVER 
THE ENTIRE CARIBBEAN SEA BRINGING STRONG SUBSIDENCE OF AIR THAT 
IS PREVENTING ANY CONVECTION ACROSS THE REGION. SURFACE EASTERLY 
WINDS OF 5 TO 15 KTS ARE NOTED OVER THE EAST AND CENTRAL 
CARIBBEAN. WEAK CYCLONIC FLOW IS OVER THE NW CORNER DUE TO THE 
PASSAGE OF THE WEAKENING TAIL END OF THE COLD FRONT. 
ELSEWHERE...CONDITIONS WILL REMAIN CONSTANT OVER THE NEXT 24 
HOURS.

THE ATLANTIC OCEAN...
A COLD FRONT HAS ENTERED THE WESTERN ATLANTIC...CURRENTLY 
LOCATED OVER THE NORTHERN BAHAMAS ALONG 32N74W 26N76W 23N80W 
CONTINUING INTO CENTRAL CUBA. MODERATE CONVECTION IS 80 NM EAST 
OF THE FRONT FROM 27N TO 32N BETWEEN 67W TO 74W. ANOTHER COLD 
FRONT IS OVER THE CENTRAL ATLANTIC ALONG 32N30W 23N40W 20N50W TO 
20N55W...WHERE IT BECOMES STATIONARY TO 20N65W. MODERATE 
CONVECTION IS 50 NM EAST OF THE FRONT FROM 26N TO 32N BETWEEN 
28W AND 34W. GALE FORCE WINDS ARE MEASURED BEHIND THE FRONT 
NORTH OF 28N EAST OF 50W. LOOK FOR GALE FORCE WINDS BEHIND THE 
THIS FRONT AS IT MOVES EASTWARD OVER THE NEXT 24 HOURS. A 1018 
MB HIGH IS CENTERED NEAR 23N20W. IN THE UPPER LEVELS...A RIDGE 
IS OVER THE WESTERN ATLANTIC...FOLLOWED BY A TROUGH OVER THE 
CENTRAL ATLANTIC AND ANOTHER RIDGE OVER THE EASTERN ATLANTIC. IN 
THE TROPICS AN UPPER LEVEL HIGH IS CENTERED NEAR THE CAPE VERDE 
ISLANDS AT 15N27W. EXPECT OVER THE NEXT 24 HOURS FOR THE TWO 
COLD FRONTS TO CONTINUE TO MOVE EASTWARD WITH SHOWERS AND 
CONVECTION. 

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

$$

GARCIA