000
AXNT20 KNHC 241039
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
805 AM EDT SAT APR 24 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1015 UTC...

...ITCZ...
THE ITCZ IS CENTERED ALONG 7N9W 4N19W 2N34W 1N52W. SCATTERED 
MODERATE/STRONG CONVECTION IS WITHIN 180 NM S OF THE ITCZ 
BETWEEN 13W-17W. CLUSTERS OF SCATTERED MODERATE/STRONG 
CONVECTION ARE WITHIN 150/180 NM N OF THE ITCZ BETWEEN 20W-36W. 
CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE 
WITHIN 150 NM S OF THE ITCZ BETWEEN 10W-22W...WITHIN 180 NM S OF 
THE ITCZ BETWEEN 30W-45W..AND WITHIN 250 NM N OF THE ITCZ 
BETWEEN 36W-43W. 

...DISCUSSION...

GULF OF MEXICO...
A BROAD UPPER TROUGH COVERS THE CENTRAL PLAINS STATES INTO THE E 
US WITH A SHORTWAVE UPPER TROUGH MOVING OVER THE MISSISSIPPI 
VALLEY. THE ASSOCIATED FRONTAL SYSTEM REMAINS INLAND OVER THE US 
WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE NE GULF 
COAST FROM MISSISSIPPI TO THE FLORIDA PANHANDLE AND ALONG THE 
IMMEDIATE COASTAL WATERS. A BROAD HIGH AMPLITUDE UPPER RIDGE 
AXIS EXTENDS FROM THE E PACIFIC REGION ACROSS S MEXICO AND THE 
YUCATAN PENINSULA NEAR 20N89W TO THE NE GULF COAST NEAR 31N85W 
DOMINATING ALL OF THE GULF WATERS. THIS UPPER FLOW IS DRAWING 
TROPICAL MOISTURE ACROSS MEXICO TO OVER THE GULF GENERATING 
SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 175 
NM OF LINE FROM OVER MEXICO N OF TAMPICO NEAR 23N98W TO 27N89W 
INCLUDING INLAND OVER LOUISIANA. A COLD FRONT IS EXPECTED TO 
ENTER THE NW GULF LATER THIS MORNING. 

CARIBBEAN SEA...
THE UPPER RIDGE OVER THE GULF OF MEXICO COVERS THE NW CARIBBEAN 
WITH A SECOND UPPER RIDGE ANCHORED OVER TROPICAL ATLC COVERING 
THE REMAINDER OF THE CARIBBEAN INDUCING A WEAK UPPER TROUGH THAT 
EXTENDS ALONG A LINE FROM E CUBA NEAR 20N75W ACROSS JAMAICA TO 
THE TIP OF NICARAGUA/HONDURAS. UPPER LEVEL MOISTURE FROM THE 
GULF OF MEXICO COVERS THE FAR NW CARIBBEAN AND SIMILAR UPPER 
LEVEL MOISTURE COVERS THE S CARIBBEAN GIVING THOSE AREAS HIGH 
CLOUDS AND LEAVING THE CENTRAL CARIBBEAN FAIRLY DRY. THE 
PRESSURE GRADIENT BETWEEN THE LOW PRESSURE OVER THE TROPICS AND 
THE SURFACE RIDGE OVER THE W ATLC IS GIVING THE CARIBBEAN 
MODERATE TO FRESH TRADE WINDS ACROSS THE AREA USHERING IN LOW 
LEVEL FAST MOVING ISOLATED SHOWERS MAINLY N OF 16N E OF 74W TO 
OVER THE LEEWARD ISLANDS INCLUDING PUERTO RICO AND HISPANIOLA.  

ATLANTIC OCEAN...
A SURFACE RIDGE COVERS THE W ATLC ANCHORED BY A 1019 MB HIGH NE 
OF THE BAHAMAS NEAR 27N75W. A BROAD LOW AMPLITUDE UPPER TROUGH 
COVERS THE W ATLC INTO THE CENTRAL ATLC SUPPORTING A DISSIPATING 
COLD FRONT THAT ENTERS THE CENTRAL ATLC NEAR 32N47W EXTENDING SW 
TO 27N54W WITH POSSIBLE ISOLATED SHOWERS WITHIN 45 NM E OF THE 
FRONT. A WEAKER UPPER TROUGH IS OVER THE E ATLC SUPPORTING A 
WEAKENING COLD FRONT ENTERING THE REGION NEAR 32N22W EXTENDING 
SW TO 29N26W DISSIPATING TO 27N30W. THIS FRONT CONTINUES TO 
BISECT A SURFACE RIDGE WITH A 1017 MB HIGH BEHIND THE FRONT 
NEAR 31N29W AND A 1018 MB HIGH SE OF THE FRONT NEAR 29N21W. THE 
UPPER RIDGE ANCHORED OVER THE TROPICAL ATLC NEAR 7N41W COVERS 
THE CARIBBEAN AS WELL AS THE E AND CENTRAL ATLC AND PROVIDING 
DIFFLUENCE ALOFT TO GENERATE CLUSTERS OF SCATTERED SHOWERS AND 
POSSIBLE ISOLATED THUNDERSTORMS WITHIN 200 NM OF LINE FROM 
21N49W TO BEYOND 32N37W.   

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

$$
WALLACE