000
AXNT20 KNHC 051753
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 PM EST TUE JAN 05 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1715 UTC.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 8N13W 3N27W 2N42W THEN TO THE 
EQUATOR NEAR 51W. ISOLATED MODERATE CONVECTION IS FROM 4N-7N 
BETWEEN 18W-21W.

...DISCUSSION...

GULF OF MEXICO...
AN EXPANSIVE SURFACE RIDGE COVERS THE GULF OF MEXICO ANCHORED BY 
A 1034 MB HIGH OVER EASTERN OKLAHOMA PROVIDING THE GULF WITH 
NORTHERLY WINDS UP TO 20 KT THAT ARE FORECAST TO GRADUALLY 
DIMINISH THROUGH WED. AN UPPER LEVEL SHORTWAVE TROUGH EXTENDS 
ALONG THE EASTERN U.S. SEABOARD ACROSS NORTHERN FLORIDA INTO THE 
FAR NE GULF WITH ANOTHER SURGE OF COOLER AND DRIER AIR FILTERING 
INTO THE EASTERN GULF...FLORIDA PENINSULA...AND W ATLC THROUGH 
THE REMAINDER OF TUESDAY. UPPER LEVEL ZONAL FLOW IS FOUND ACROSS 
THE REMAINDER OF THE GULF BETWEEN THE UPPER LEVEL TROUGHING 
ACROSS THE EASTERN CONUS AND AN UPPER LEVEL ANTICYCLONIC 
CIRCULATION CENTERED OVER SOUTHERN CENTRAL AMERICA. MIDDLE TO 
UPPER LEVEL MOISTURE CONTINUES TO STREAM ACROSS CENTRAL MEXICO 
AND THE SOUTHERN GULF S OF 25N WITH ISOLATED SHOWERS POSSIBLE 
ACROSS THE SW GULF S OF 22N W OF 90W.

CARIBBEAN SEA...
A SURFACE TROUGH CROSSES HISPANIOLA FROM THE W ATLC AND ENTERS 
THE CARIBBEAN AS A SHEAR LINE FROM SW HAITI NEAR 18N74W TO 
15N80W TO 10N83W. N TO NE WINDS NORTH OF THE BOUNDARY AND 
EASTERLY TRADES ACROSS THE CENTRAL CARIBBEAN ARE CONVERGING TO 
PRODUCE ISOLATED SHOWERS PRIMARILY NW OF A LINE FROM SW HAITI TO 
THE COAST OS COSTA RICA. THIS ACTIVITY IS LOCATED ON THE 
NORTHERN SIDE OF BROAD UPPER LEVEL ANTICYCLONIC CIRCULATION 
CENTERED OVER WESTERN PANAMA NEAR 8N82W THAT COVERS THE ENTIRE 
CARIBBEAN BASIN. STRONG SUBSIDENCE AND DRY STABLE AIR IS NOTED 
ON WATER VAPOR IMAGERY MAINLY S OF 16N WITH CLEAR SKIES OBSERVED 
E OF THE SHEAR LINE. 

ATLANTIC OCEAN...
A DEEP LAYERED TROUGH IS OVER THE W ATLC INTO THE CENTRAL ATLC 
AND SUPPORTS A SURFACE TROUGH EXTENDING FROM NEAR 31N49W SW 
ALONG 25N63W TO THE COAST OF HISPANIOLA NEAR 20N70W. LOW-LEVEL 
CONVERGENCE NEAR THE SURFACE TROUGH IS GENERATING SCATTERED 
SHOWERS WITHIN 120 NM EITHER SIDE OF THE BOUNDARY. BEHIND THIS 
WEAKENING BOUNDARY...A COLD FRONT IS DRAPED FROM 31N63W TO 
25N74W WITH SCATTERED SHOWERS LOCATED WITHIN 120 NM EITHER SIDE 
OF THE FRONT. WEST WINDS TO GALE FORCE ARE EXPECTED BEHIND THE 
FRONT BY LATE TONIGHT. THE MAIN UPPER LEVEL SUPPORT FOR THIS 
FRONT IS AN UPPER LEVEL SHORTWAVE TROUGH WITH AXIS OVER THE FAR 
W ATLC FROM 32N72W TO 27N80W. ELSEWHERE...A SURFACE RIDGE 
DOMINATES THE REMAINDER OF THE ATLC ANCHORED BY A 1027 MB HIGH  
CENTERED NEAR 27N34W GIVING A MAJORITY OF THE EASTERN ATLC FAIR 
WEATHER. THIS SURFACE HIGH IS SUPPORTED ALOFT BY AN UPPER LEVEL 
RIDGE AXIS THAT EXTENDS FROM THE EASTERN CARIBBEAN SEA NEAR 
PUERTO RICO ALONG 21N50W TO BEYOND 32N36W. 

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

$$
HUFFMAN