000 AXNT20 KNHC 311153 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU MAY 31 2012 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1100 UTC. ...TROPICAL WAVES... TROPICAL WAVE HAS EMERGED OFF THE COAST OF AFRICA AND EXTENDS FROM 10N20W TO 3N21W. UPPER AIR TIME-SECTION DATA FROM DAKAR SENEGAL INDICATES THAT THE WAVE MOVED OFF THE COAST ABOUT 12 HOURS AGO AND IS MOVING W NEAR 15-20 KTS. THE WAVE LIES W OF A SURGE IN DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. GOES-R DUST ENHANCEMENT IMAGERY ALSO INDICATES THAT THERE IS A CLEARING OF DUST AROUND THE WAVE IN THE AREA OF DUST THAT HAS BEEN MOVING ACROSS THE TROPICAL ATLC. VERY ISOLATED MODERATE CONVECTION IS NEAR THE AXIS. TROPICAL WAVE IS ALONG 13N57W TO 7N59W MOVING W AT 5-10 KT. THE WAVE LIES IN AN AREA OF MAXIMUM MOISTURE PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. AN UPPER LEVEL TROUGH COINCIDES WITH THE WAVE AND IS ENHANCING CONVECTION NEAR THE AXIS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 11N-15N BETWEEN 55W-59W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS W AFRICA TO THE COAST OF GUINEA-BISSAU AT 12N16W TO 7N18W. THE ITCZ CONTINUES ON THE W SIDE OF A TROPICAL WAVE AND EXTENDS ALONG 4N23W 2N38W 3N54W. SCATTERED MODERATE CONVECTION IS FROM 4N-6N BETWEEN 23W-31W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 4N-9N BETWEEN 47W-52W. ...DISCUSSION... GULF OF MEXICO... DRY AIR ALOFT COVERS THE MAJORITY OF THE GULF OF MEXICO AROUND AN UPPER LEVEL TROUGH EXTENDING FROM LOUISIANA TO THE BAY OF CAMPECHE. THIS DRY AIR ACCOMPANIED BY SURFACE RIDGING AROUND A WEAK 1014 MB HIGH NEAR 27N87W IS HELPING MAINTAIN MOSTLY CLEAR SKIES ACROSS THE BASIN. LIGHT ANTI-CYCLONIC FLOW IS AROUND THE HIGH CENTER WITH STRONGER SLY WINDS UP TO 20 KTS ACROSS THE FAR WRN GULF. DESPITE DRY AIR ACROSS MOST OF THE BASIN...A LARGE AREA OF DEEP LAYER MOISTURE COMBINED WITH DIFFLUENCE ALOFT AROUND THE E SIDE OF THE UPPER TROUGH IS HELPING SUPPORT SCATTERED SHOWERS/THUNDERSTORMS ACROSS THE SE GULF S OF 26N E OF 90W. A SURFACE TROUGH ANALYZED FROM 24N83W TO 19N90W IS ALSO ENHANCING SOME OF THE ACTIVITY. THE AREA OF MOISTURE IN THE SE GULF IS EXPECTED TO CONTINUE TO DRIFT NWD OVER THE NEXT 24 WITH POSSIBLE HEAVY RAIN ACROSS PORTIONS OF S FLORIDA. CARIBBEAN SEA... UPPER LEVEL DIFFLUENCE BETWEEN AN UPPER LEVEL TROUGH W OF THE YUCATAN PENINSULA AND AN UPPER LEVEL RIDGE ACROSS THE CARIBBEAN ALONG 78W IS PROVIDING MOIST CONDITIONS ACROSS THE WRN CARIBBEAN. CURRENTLY A CLUSTER OF STRONG SHOWERS/THUNDERSTORMS IS NEAR THE ERN COAST OF THE YUCATAN PENINSULA FROM 17N-21N BETWEEN 86W-89W. THIS ACTIVITY IS ALSO ENHANCED BY A SURFACE TROUGH EXTENDING FROM THE YUCATAN PENINSULA TO N OF WRN CUBA. ISOLATED SHOWERS ARE ACROSS THE REMAINDER OF THE W ATLC. HOWEVER...STRONG SHOWERS/THUNDERSTORMS ARE ALSO ACROSS PORTIONS OF CENTRAL AMERICA INCLUDING NICARAGUA AND COAST RICA ASSOCIATED WITH THE E PACIFIC MONSOON TROUGH EXTENDING ACROSS COSTA RICA AND PANAMA TO A 1010 MB LOW OVER NRN COLOMBIA AT 10N72W. MODERATE DRY AIR ALOFT COVERS THE CENTRAL AND ERN CARIBBEAN AROUND THE E SIDE OF THE UPPER RIDGE ACROSS THE BASIN PROVIDING MOSTLY CLEAR SKIES ACROSS THIS AREA. TRADEWIND FLOW OF 15-20 KTS COVERS THE MAJORITY OF THE BASIN. AN AREA OF MOISTURE CONTINUES TO MOVE THROUGH THE SE CARIBBEAN AHEAD OF A TROPICAL WAVE STILL E OF THE ISLANDS. ISOLATED SHOWERS/POSSIBLE THUNDERSTORMS ARE S OF 15N E OF 65W. MOIST CONDITIONS ARE EXPECTED TO REMAIN OVER THE WRN CARIBBEAN THROUGH AT LEAST THE NEXT 24 HOURS. ATLANTIC... A SURFACE TROUGH IS E OF N FLORIDA ALONG 32N74W TO 30N78W SUPPORTING A FEW CLUSTERS OF SHOWERS/THUNDERSTORMS ALONG THE AXIS AND FROM 30N-31N BETWEEN 78W-80W. ISOLATED SHOWERS ALSO COVER MUCH OF THE BAHAMAS S OF 27N BETWEEN 69W-81W ASSOCIATED WITH DEEP LAYER MOISTURE WRAPPING AROUND AN UPPER LEVEL RIDGE ACROSS THE CARIBBEAN WHICH THEN EXTENDS NWD ALONG 68W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE ALSO FROM 26N-30N BETWEEN 70W-73W. AN UPPER LEVEL TROUGH ALONG 58W IS SUPPORTING CLUSTERS OF SHOWERS/THUNDERSTORMS FROM 18N-27N BETWEEN 55W-61W. THE UPPER TROUGH ALSO SUPPORTS A SURFACE TROUGH ALONG 28N52W TO 29N61W SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS WITHIN 90 NM TO THE N. THE UPPER TROUGH IS ALSO ENHANCING CONVECTION NEAR A TROPICAL WAVE E OF THE WINDWARD ISLANDS. A WEAK UPPER RIDGE IS ALONG 47W SUPPORTING A 1022 MB HIGH NEAR 24N44W WHICH IS PROVIDING FAIR CONDITIONS ACROSS MUCH OF THE CENTRAL AND ERN ATLC. AN UPPER LEVEL TROUGH COVERS THE NE ATLC ALONG 29W...BUT IS CAUSING NO SIGNIFICANT WEATHER IN THE DISCUSSION AREA. A BROAD UPPER RIDGE COVERS THE TROPICAL ATLC CENTERED NEAR 13N34W MAINTAINING FAIR CONDITIONS AND LITTLE CONVECTION NEAR THE ITCZ. GOES-R DUST ENHANCEMENT IMAGERY CONTINUES TO SHOW AN AREA OF SAHARAN DUST EXTENDING FROM THE COAST OF AFRICA TO NEAR 45W WHICH FURTHER SUPPORTS A STABLE ENVIRONMENT AND FAIR CONDITIONS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON