000 AXNT20 KNHC 092354 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU JUN 09 2011 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2245 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS IN THE CENTRAL ATLC EXTENDING FROM 11N30W TO 4N34W MOVING W 10-15 KT. THE WAVE IS JUST W OF A RIDGE OF ENHANCED MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. BROAD CYCLONIC FLOW IS AROUND THE WAVE AXIS INDICATED IN VISIBLE SATELLITE IMAGERY AND SATELLITE DERIVED WINDS. NO DEEP CONVECTION IS CURRENTLY ASSOCIATED WITH THE WAVE. ...ITCZ/MONSOON TROUGH... MONSOON TROUGH AXIS EXTENDS FROM THE PRIME MERIDIAN NEAR 15N TO 16N13W SWD TO THE GUINEA COAST AT 10N14W CONTINUING TO NEAR 5N20W. ITCZ CONTINUES FROM 5N20W ALONG 8N31W 6N45W 8N58W. ISOLATED MODERATE CONVECTION IS WITHIN 150 NM S OF THE AXIS BETWEEN 20W-30W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM N OF THE AXIS BETWEEN 42W-47W. ...DISCUSSION... THE GULF OF MEXICO... SCATTERED SHOWERS/THUNDERSTORMS HAVE FLARED UP ACROSS THE N CENTRAL GULF COAST N OF 29N BETWEEN 89W-94W MAINLY ACROSS SRN LOUISIANA...WITH ISOLATED SHOWERS/THUNDERSTORMS S OF 29N TO 24N BETWEEN 85W-92W. SCATTERED SHOWERS/THUNDERSTORMS HAVE ALSO FLARED UP OVER WRN CUBA AND THE NRN YUCATAN PENINSULA. ISOLATED SHOWERS ARE ACROSS THE FLORIDA STRAITS AS MOISTURE FROM THE NW CARIBBEAN IS FINALLY SHIFTING N. HOWEVER...MOST OF THE HEAVIER SHOWER ACTIVITY IS E OF S FLORIDA. THE REMAINDER OF THE GULF IS UNDER MOSTLY FAIR CONDITIONS UNDER THE INFLUENCE OF WEAK SURFACE RIDGING FROM A 1017 MB HIGH OVER MISSISSIPPI...AND DRY AIR ALOFT WRAPPING AROUND THE WRN AND SRN SIDES OF AN ELONGATED UPPER LEVEL LOW CENTERED IN THE NE GULF NEAR 27N86W WITH UPPER TROUGH AXIS EXTENDING FROM GEORGIA TO THE YUCATAN PENINSULA. UPPER LEVEL CLOUDS COVER THE SRN HALF OF FLORIDA DUE TO MOISTURE FLOWING AROUND THE ERN SIDE OF THE UPPER TROUGH. EXPECT A POSSIBLE INCREASE IN SHOWERS/THUNDERSTORMS OVER THE SE GULF AS BROAD LOW PRESSURE IN THE CARIBBEAN DRIFTS N WITH LITTLE CHANGE ELSEWHERE ACROSS THE BASIN. THE CARIBBEAN SEA... BROAD CYCLONIC FLOW CONTINUES TO DOMINATE THE NW CARIBBEAN DUE TO FLOW AROUND A 1010 MB SURFACE LOW NEAR 19N84W. MOST OF THE SHOWER ACTIVITY IS NE OF THE LOW CENTER NEAR A SURFACE TROUGH EXTENDING FROM THE W ATLC ACROSS THE CENTRAL BAHAMAS AND CENTRAL CUBA THROUGH THE LOW CENTER TO NEAR 18N85W. NUMEROUS SHOWERS/SCATTERED THUNDERSTORMS ARE FROM 20N-23N BETWEEN 76W-80W MAINLY IMPACTING CENTRAL CUBA. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO ACROSS WRN CUBA. SOME OF THIS ACTIVITY IS INFLUENCED BY DIFFLUENCE ALOFT BETWEEN AN UPPER LEVEL TROUGH OVER THE GULF OF MEXICO AND AN UPPER LEVEL RIDGE ACROSS THE CARIBBEAN. A WEAK SHORTWAVE UPPER TROUGH EXTENDS OVER THE BAHAMAS FROM NW TO SE INTRUDING INTO THE UPPER RIDGE CAUSING THERE TO BE TWO ANTI-CYCLONIC CENTERS...ONE S OF JAMAICA NEAR 17N76W...AND THE SECOND N OF PUERTO RICO NEAR 20N67W. THE SHORTWAVE TROUGH SUPPORTS ANOTHER BURST OF NUMEROUS SHOWERS/SCATTERED THUNDERSTORMS OVER HISPANIOLA FROM 18N-20N BETWEEN 68W-72W. BOTH CUBA AND HISPANIOLA HAVE RECEIVED HIGH AMOUNTS OF PRECIPITATION OVER THE PAST SEVERAL DAYS. THIS ADDED HEAVY RAINFALL INCREASES THE POTENTIAL FOR FLOODING AND MUDSLIDES. A FEW ISOLATED SHOWERS/THUNDERSTORMS ARE ALSO ACROSS PUERTO RICO AND THE VIRGIN ISLANDS N OF 17N E OF 68W. SOME OF THIS ACTIVITY IS SUPPORTED BY A SECOND SURFACE TROUGH EXTENDING FROM THE CENTRAL ATLC TO THE VIRGIN ISLANDS NEAR 18N65W. MODERATE DRY AIR ALOFT AROUND THE S SIDE OF THE UPPER RIDGE IS SUPPORTING FAIR CONDITIONS S OF 16N ACROSS THE ENTIRE CARIBBEAN. EXPECT SHOWER ACTIVITY TO CONTINUE ACROSS THE NRN CARIBBEAN...ESPECIALLY THE NW PORTION OVER THE NEXT 24 HOURS AS THE BROAD AREA OF LOW PRESSURE CONTINUES TO DRIFT N. THE ATLANTIC OCEAN... A WEAK SURFACE RIDGE IS OVER THE WRN ATLC AROUND A 1020 MB HIGH NEAR 30N70W SUPPORTED BY AN UPPER LEVEL RIDGE EXTENDING FROM THE CARIBBEAN ALONG 70W. HOWEVER...UPPER LEVEL DIFFLUENCE BETWEEN THIS UPPER RIDGE AND AN UPPER LEVEL TROUGH OVER THE GULF OF MEXICO IS SUPPORTING A LARGE AREA OF SHOWERS/POSSIBLE THUNDERSTORMS FROM CUBA TO N OF THE BAHAMAS S OF 26N BETWEEN 68W-80W. THE ACTIVITY IS STRONGEST JUST N OF CUBA. SOME OF THE ACTIVITY IS ALSO INFLUENCED BY A SURFACE TROUGH EXTENDING FROM NEAR 25N74W ACROSS THE CENTRAL BAHAMAS TO CENTRAL CUBA NEAR 22N78W. A DEEP LAYER TROUGH TO THE E IS SUPPORTING ANOTHER SURFACE TROUGH ENTERING THE DISCUSSION AREA NEAR 32N45W ALONG 27N50W THROUGH A 1013 MB SURFACE LOW NEAR 23N60W TO THE VIRGIN ISLANDS NEAR 18N65W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 250 NM E OF THE TROUGH AXIS N OF 24N AND FROM 18N-24N BETWEEN 53W-59W. THE REMAINDER OF THE BASIN IS DOMINATED BY SURFACE RIDGING EXTENDING FROM A 1026 MB HIGH S OF THE AZORES ISLANDS. ALOFT...AN UPPER LEVEL RIDGE EXTENDS FROM N OF ERN S AMERICA TO JUST W OF THE AZORES. AN UPPER LEVEL TROUGH IS TO THE E EXTENDING FROM PORTUGAL TO NEAR 20N32W. ANOTHER UPPER LEVEL RIDGE DOMINATES THE TROPICAL ATLC CENTERED OVER THE W AFRICAN COAST NEAR 16N16W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON