000
AXNT20 KNHC 031058
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST SAT JAN 03 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1015 UTC.

...THE ITCZ...

ITCZ IS CENTERED ALONG 7N9W 4N18W 3N46W 2N52W. CLUSTERS OF 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 7N TO 
JUST S OF THE EQUATOR E OF 22W TO ACROSS THE PRIME MERIDIAN. 

...DISCUSSION...

GULF OF MEXICO...
UPPER LEVEL WLY ZONAL FLOW IS ACROSS THE GULF ADVECTING UPPER 
LEVEL MOISTURE FROM THE E PACIFIC ACROSS MEXICO AND THE GULF N 
OF 24N GENERATING SCATTERED/HEAVY SHOWERS N OF 26N W OF 94W TO 
INLAND OVER E TEXAS AND ISOLATED SHOWERS N OF 25N W OF 90W. A 
JET STREAM WITH WINDS OF 80 TO 100 KT IS ALSO ACROSS THE N GULF 
AND FLORIDA BETWEEN 24N AND 29N. A SURFACE RIDGE REMAINS OVER 
THE GULF ANCHORED IN THE W ATLC GIVING THE ENTIRE GULF SLY 
SURFACE RETURN FLOW. THIS IS GENERATING ISOLATED SHOWERS MAINLY 
S OF 26N E OF 87W. PATCHES OF FOG ARE BEING REPORTED ACROSS THE 
N GULF COAST STATES FROM TALLAHASSEE FLORIDA TO THE LOUISIANA/ 
TEXAS BORDER. THE NEXT COLD FRONT IS EXPECTED TO ENTER THE GULF 
LATE SUN.

CARIBBEAN SEA...
A BROAD UPPER RIDGE ANCHORED OVER SOUTH AMERICA IS GIVING THE 
CARIBBEAN SW TO W UPPER FLOW. STRONG SUBSIDENCE AND DRY STABLE 
AIR CONTINUE TO DOMINATE THE CARIBBEAN W OF 68W. THE REMNANTS OF 
A SURFACE TROUGH REMAIN OVER THE SE CARIBBEAN GENERATING LOW/MID 
LEVEL CLOUDS WITH EMBEDDED SCATTERED SHOWERS ACROSS THE AREA S 
OF 17N E OF 68W TO ACROSS THE LESSER ANTILLES. ELSEWHERE... 
MODERATE TRADE WINDS ARE PRODUCING AN AREA OF ISOLATED SHOWERS 
FROM 15N-19N BETWEEN 79W-85W AND CONTINUE TO USHER IN ISOLATED 
FAST MOVING SHOWERS OVER THE REMAINDER OF THE CARIBBEAN. 

ATLANTIC...
A WEAK UPPER TROUGH DIPS S OVER THE W ATLC N OF 26N FROM 60W TO 
THE NE FLORIDA. A WEAKENING SURFACE RIDGE COVERS THE W ATLC 
ANCHORED BY A 1024 MB HIGH CENTERED NEAR 31N55W. A DEEP LAYERED 
UPPER LEVEL TROUGH IS ACROSS THE N/CENTRAL ATLC N OF THE REGION 
SUPPORTING A COLD FRONT ENTERING THE REGION NEAR 32N41W TO 
27N50W WHERE IT BECOMES STATIONARY TO THE E BAHAMAS NEAR 24N76W. 
SCATTERED SHOWERS ARE ARE N OF 28N WITHIN 120/150 NM E OF THE 
FRONT WITH PATCHES OF BROKEN/OVERCAST LOW CLOUDS AND ISOLATED 
SHOWERS WITHIN 90 NM ON EITHER SIDE OF THE FRONTAL BOUNDARY W OF 
45W. A JETSTREAM WITH WINDS OF 80 TO 100 KT IS ACROSS THE W ATLC 
WITHIN 150/200 NM OF LINE FROM ACROSS THE GULF OF MEXICO AND 
FLORIDA NEAR 26N80W 25N66W TO BEYOND 32N53W. UPPER WESTERLY 
ZONAL FLOW DOMINATES THE REMAINDER OF THE ATLC. E OF THE FRONT 
OVER THE E ATLC...A SURFACE RIDGE IS ANCHORED BY A 1027 MB HIGH 
NEAR 34N24W.

$$
WALLACE