000
AXNT20 KNHC 261038
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
805 AM EDT SAT MAR 26 2011

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTION 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.

...ITCZ...

ITCZ AXIS IS ANALYZED ALONG 7N11W 3N20W 2N28W CROSSING THE 
EQUATOR NEAR 34W CONTINUING SOUTH OF THE EQUATOR TO INLAND OVER 
SOUTH AMERICA. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS 
FROM 2N TO THE COAST OF SW AFRICA BETWEEN 4W-7W. SMALL CLUSTERS 
OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 
30/45 NM OF 3N BETWEEN 21W-27W.

...DISCUSSION...

GULF OF MEXICO...
A BROAD UPPER RIDGE THAT DOMINATES THE CARIBBEAN AND ANCHORED IN 
THE TROPICS COVERS THE GULF OF MEXICO WITH SW TO W FLOW ALOFT. 
MODERATE SUBSIDENCE AND DRY STABLE AIR COVER THE GULF WATERS S 
OF 25N. A WEAK SURFACE RIDGE OVER THE ATLC COVERS THE E GULF 
GIVING THE GULF SW TO S SURFACE FLOW BANKING SOME LOW LEVEL 
CLOUDS WITH POSSIBLE ISOLATED SHOWERS OVER THE GULF MAINLY N OF 
23N W OF 93W AND N OF 29N BETWEEN 86W-93W LEAVING THE REMAINDER 
OF THE GULF WITH MOSTLY CLEAR SKIES AGAIN THIS MORNING. AS THE 
WEAK HIGH PRESSURE CONTINUES TO SHIFT SE...RETURN FLOW WILL 
BECOME MORE S TO SE TOADY. RIDGE WILL WEAKEN FURTHER ON SUN AS A 
COLD FRONT STALLS OVER THE NORTHERN COASTAL PLAINS AND 
DISSIPATES MON. 

CARIBBEAN SEA...
BROAD UPPER RIDGE ANCHORED OVER THE TROPICS COVERS THE CARIBBEAN 
AND GULF OF MEXICO GIVING THE CARIBBEAN SW TO W FLOW ALOFT. 
STRONG SUBSIDENCE AND DRY STABLE AIR COVERS THE W CARIBBEAN W OF 
LINE FROM HAITI TO CENTRAL PANAMA WHILE THE SW FLOW ALOFT IS 
DRAWING TROPICAL MOISTURE OVER THE E CARIBBEAN. REMNANT LOW 
LEVEL MOISTURE REMAINS ACROSS THE CENTRAL CARIBBEAN DEVELOPING 
SCATTERED SHOWERS MAINLY S OF 18N BETWEEN 75W-86W WITH ISOLATED 
SHOWERS N OF 15N E OF 75W TO OVER THE LEEWARD/VIRGIN ISLANDS... 
PUERTO RICO AND HISPANIOLA. EASTERLY TRADES WILL WEAKEN THROUGH 
TODAY AS THE ATLC RIDGE N OF AREA SHIFTS S. TRADES WILL INCREASE 
AGAIN STARTING SUN THROUGH MIDWEEK. 

ATLANTIC OCEAN...
AN UPPER TROUGH IS OVER THE NW ATLC N OF 29N W OF 50W SUPPORTING 
A COLD FRONT THAT EXTENDS ALONG 32N49W TO 29N54W WHERE IT BEGINS 
TO DISSIPATE ALONG 28N61W TO 29N66W. SCATTERED SHOWERS ARE 
WITHIN 60 NM E OF THE COLD FRONT N OF 29N. A BROAD SURFACE RIDGE 
COVERS MOST OF THE ATLC WITH AN AXIS EXTENDING FROM A 1021 MB 
HIGH NEAR 26N40W THROUGH A WEAK 1017 MB HIGH LOCATED E OF THE 
BAHAMAS NEAR 23N67W TO OVER CENTRAL CUBA NEAR 22N80W. IN THE E 
ATLC IS A WEAK SURFACE TROUGH EXTENDING FROM 28N34W TO 23N37W 
WITH POSSIBLE ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF THE 
SURFACE TROUGH. BROAD SURFACE RIDGE DOMINATES THE REMAINDER OF 
THE ATLC WITH A WEAKNESS IN THE VICINITY OF THE ABOVE SURFACE 
TROUGH AND A 1023 MB HIGH LOCATED NEAR 30N25W. THIS SURFACE 
RIDGE CONTINUES TO GIVE THE ATLC MOSTLY FAIR WEATHER AGAIN THIS 
MORNING. SURFACE RIDGE ACROSS N BAHAMAS WILL SHIFT E ON SUN IN 
ADVANCE OF COLD FRONT MOVING INTO NW WATERS SUN NIGHT. FRONT 
WILL EXTEND FROM BERMUDA TO CENTRAL FLORIDA LATE MON. 

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

$$
PAW