000
AXNT20 KNHC 081735
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
205 PM EDT SAT MAY 08 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...

...TROPICAL WAVES...
TROPICAL WAVE IS FROM 9N21W TO 2N19W MOVING W NEAR 10 KT. WELL 
DEFINED ROTATION IS OBSERVED IN THE VISIBLE SATELLITE IMAGERY. 
CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE 
WITHIN 45 NM OF LINE FROM 6N17W 7N20W 6N22W. 

TROPICAL WAVE IS ALONG 37W S OF 5N MOVING W 5-10 KT. ILL-DEFINED 
WAVE WITH NO ASSOCIATED CONVECTION. 

TROPICAL WAVE IS ALONG 47W/48W S OF 9N MOVING W 5-10 KT. WELL 
DEFINED ROTATION IS OBSERVED IN THE INFRARED SATELLITE IMAGERY 
WITH CLUSTERS OF SCATTERED MODERATE CONVECTION WITHIN 120/150 NM 
W OF THE WAVE AXIS FROM 2N8N. 

...THE ITCZ...

ITCZ AXIS IS CENTERED ALONG 7N11W 3N31W 5N50W 4N54W. SCATTERED 
MODERATE CONVECTION IS FROM 8N-10N BETWEEN 14W-17W...FROM 3N TO 
S OF THE EQUATOR BETWEEN 15W-18W...AND FROM 4N TO S OF THE 
EQUATOR BETWEEN 39W-42W. 

...DISCUSSION...

GULF OF MEXICO...
THE ANTICIPATED COLD FRONT ENTERED THE NW GULF AT 1200 UTC TODAY 
AND AT 08/1500 UTC IS ACROSS THE MISSISSIPPI COAST OVER NEW 
ORLEANS LOUISIANA INTO THE NW GULF NEAR VERMILION BAY TO INLAND 
OVER TEXAS BETWEEN GALVESTON AND CORPUS CHRIST. THIS FRONT IS 
MOVING SLOWLY WHILE THE WESTERN PORTION IS BECOMING NEAR 
STATIONARY AND ISOLATED SHOWERS ALONG THE FRONTAL BOUNDARY. THE 
UPPER LEVEL SUPPORT FOR THIS FRONT IS OVER THE NE US WITH THE 
UPPER LOW OVER THE GREAT LAKES. THE GULF WATERS ARE DOMINATE BY 
AN UPPER LEVEL RIDGE THAT EXTENDS FROM THE BAY OF CAMPECHE TO 
THE BIG BEND AREA OF FLORIDA. THIS UPPER RIDGE IS BRINGING DRY 
STABLE AIR WITH STRONG SUBSIDENCE OVER THE S GULF. ALSO AT 
08/1500 UTC...A SURFACE TROUGH IS OVER THE SW GULF FROM 23N95W 
TO THE BAY OF CAMPECHE NEAR 18N94W. LOW CLOUDS ARE BANKING W OF 
THE SURFACE TROUGH TO ALONG THE E SLOPES OF THE SIERRA MADRE 
MOUNTAINS. DESPITE THE DRY AIRMASS THAT DOMINATES THE GULF...THE 
COMBINATION OF DIURNAL HEATING AND AVAILABLE LOW LEVEL MOISTURE 
COUPLED WITH THE DEVELOPING SEA BREEZE WILL CONVERGE OVER THE 
FLORIDA PENINSULA AND COULD RESULT IN AFTERNOON SHOWERS AND 
POSSIBLE THUNDERSTORMS.  

CARIBBEAN SEA...
AN UPPER RIDGE THAT COVERS THE GULF OF MEXICO COVERS THE NW 
CARIBBEAN WITH DRY STABLE AIR AND STRONG SUBSIDENCE N OF A LINE 
FROM NW HAITI TO THE N COAST OF HONDURAS TO THE YUCATAN 
PENINSULA. A SECOND UPPER RIDGE ANCHORED OVER TROPICAL ATLC 
COVERS THE E CARIBBEAN. THE TIGHT PRESSURE GRADIENT IS PROVIDING 
MODERATE/STRONG EASTERLY TRADE WINDS ACROSS THE CARIBBEAN WITH 
THE STRONGEST WINDS ALONG THE COAST OF COLOMBIA. AN UPPER LOW IS 
OVER NICARAGUA EXTENDING A TROUGH AXIS SW TO W PANAMA. THE 
SOUTHERLY UPPER FLOW AND THE EASTERLY SURFACE FLOW ARE 
CONVERGING OVER THE SW CARIBBEAN GENERATING SCATTERED 
SHOWERS/ISOLATED THUNDERSTORMS FROM 13N-15N W OF 82W TO INLAND 
OVER NICARAGUA AND WITHIN 60 NM ALONG THE COAST OF PANAMA W OF 
80W. A WEAKENING SURFACE TROUGH REMAINS OVER THE NE CARIBBEAN 
FROM PUERTO RICO INTO THE SW ATLC GENERATING SCATTERED SHOWERS N 
OF 17N BETWEEN 66W-70W. THE REMAINDER OF THE CARIBBEAN IS UNDER 
FAIR WEATHER CLOUDS THIS AFTERNOON. 

ATLANTIC OCEAN...
A WEAK SURFACE TROUGH IS IN THE FAR W ATLC EXTENDING FROM 32N78W 
TO THE COAST OF THE FLORIDA PENINSULA NEAR PALM BEACH AND IS 
GENERATING ISOLATED SHOWERS WITHIN 45 NM EITHER SIDE OF THE 
TROUGH AXIS. A WEAKENING SURFACE TROUGH EXTENDS FROM 21N64W TO 
OVER PUERTO RICO GENERATING SCATTERED SHOWERS S OF 21N BETWEEN 
63W-68W. A SECOND BETTER DEFINED SURFACE TROUGH IS ALONG 60W 
FROM 21N-25N PRODUCING ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE 
OF THE TROUGH AXIS. A BROAD SURFACE RIDGE DOMINATES THE 
REMAINDER OF THE W ATLC AND THE CENTRAL ATLC ANCHORED BY A 1022 
MB HIGH NEAR 29N48W AND GIVING THE REMAINDER OF THE AREA W OF 
30W FAIR WEATHER THIS AFTERNOON. A COLD FRONT ENTERS THE E ATLC 
NEAR 32N15W TO 28N20W WHERE IT BECOMES STATIONARY TO 26N26W AND 
DISSIPATES TO 25N32W GIVING THE AREA WITHIN 90 NM E OF THE COLD 
FRONT SCATTERED SHOWERS. 

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

$$
WALLACE