000 AXNT20 KNHC 020003 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SAT JUN 01 2013 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 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS MOVING THROUGH THE MONSOON TROUGH OFF THE COAST OF AFRICA ALONG 16N20W TO 5N24W MOVING WEST AT 10 KT. THE WAVE LIES ON THE WEST SIDE OF A SURGE OF DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. METEOSAT SAL TRACKING IMAGERY SHOW AFRICAN DUST SPREADING N OF 12N OVER THE WAVE AXIS LIMITING THE CONVECTION IN THAT REGION. WIDELY SCATTERED MODERATE CONVECTION IS NEAR THE SOUTHERN EXTENT OF THE WAVE AXIS FROM 2N-10N BETWEEN 18W-28W. TROPICAL WAVE IS ALONG 15N48W TO 6N49W MOVING WEST AT 15 KT. THE SOUTHERN REGION OF THE WAVE AXIS S OF 10N IS EMBEDDED IN A DEEP LAYER OF MOISTURE AS DEPICTED IN TOTAL PRECIPITABLE WATER IMAGERY. THERE IS NO SAL DUST ENGULFING THIS WAVE AT THIS TIME. WIDELY SCATTERED RAINSHOWERS ARE FROM 4N-15N BETWEEN 45W-52W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF SENEGAL NEAR 15N16W AND CONTINUES THROUGH A TROPICAL WAVE ALONG 13N20W 9N23W 6N33W. THE ITCZ BEGINS NEAR 6N33W AND CONTINUES ALONG 5N40W 7N47W...THEN RESUMES AFTER WAVE AXIS ALONG 7N51W TO 6N58W. BESIDES ACTIVITY NEAR THE TROPICAL WAVES...SCATTERED MODERATE CONVECTION IS FROM 4N-7N BETWEEN 33W-37W. ...DISCUSSION... GULF OF MEXICO... SURFACE AND MIDDLE TO UPPER LEVEL RIDGING DOMINATE THE GULF N OF 23N. THIS REGION IS BEING INFLUENCED BY DRY AIR ALOFT WHICH IS SUPPORTING CLEAR SKIES. A 1007 MB LOW IS LOCATED SW IN THE GULF NEAR 19N93W. DEEP LAYER MOISTURE OVER THE SOUTHERN GULF AND THE W CARIBBEAN ALONG WITH UPPER LEVEL DIVERGENCE IN THE YUCATAN CHANNEL IS SUPPORTING NUMEROUS SHOWERS/THUNDERSTORMS OVER THE YUCATAN PENINSULA...S OF 21N E OF 92W AND OVER THE YUCATAN CHANNEL. RAINSHOWERS HAVE BEEN REPORTED IN WESTERN CUBA AND EXTENDS TO THE FLORIDA STRAITS. EAST TO SOUTHEAST WINDS OF 10-15 KT ARE THROUGHOUT THE BASIN. SIMILAR WEATHER CONDITIONS ARE EXPECTED TO PERSIST WITHIN THE NEXT 24 HOURS FOR THE SW AND SE GULF AS UPPER LEVEL DIFFLUENCE AND ABUNDANT MOISTURE REMAIN IN PLACE. IN ADDITION SURFACE LOW PRESSURE IS EXPECTED TO REMAIN IN THE SW GULF. CARIBBEAN SEA... ABUNDANT DEEP LAYER MOISTURE IS THROUGHOUT THE WESTERN CARIBBEAN EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. THIS MOISTURE COMBINED WITH UPPER LEVEL DIFFLUENCE IS ENHANCING NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS N OF 19N W OF 79W...OVER CUBA AS WELL AS LA HISPANIOLA. A MIDDLE TO UPPER LEVEL SHORT-WAVE TROUGH IS OVER THE EASTERN CARIBBEAN ENHANCING SCATTERED SHOWERS OVER PUERTO RICO AND THE LESSER ANTILLES. ISOLATED SHOWERS ARE POSSIBLE OVER THE SOUTHERN CARIBBEAN S OF 12N MOSTLY ASSOCIATED WITH THE CONVECTION OF THE MONSOON TROUGH AXIS. THE REMAINDER OF THE BASIN IS MOSTLY UNDER FAIR WEATHER CONDITIONS DUE TO A TONGUE OF DRY AIR ALOFT THAT IS SUPPRESSING CONVECTION. OTHERWISE...TRADEWIND FLOW OF 15-20 KT IS PRESENT THROUGHOUT MUCH OF THE BASIN. LITTLE CHANGE IS EXPECTED OVER THE NEXT 24 HOURS WITH SIGNIFICANT MOISTURE EXPECTED TO REMAIN OVER THE WESTERN CARIBBEAN. BY 48 HOURS...A TROPICAL WAVE IN THE TROPICAL ATLC WILL HAVE REACHED THE LESSER ANTILLES BRINGING A MOIST AIRMASS WITH IT. HISPANIOLA... UPPER LEVEL DIFFLUENCE AND ABUNDANT MOISTURE OVER THE WESTERN CARIBBEAN ARE SUPPORTING NUMEROUS SHOWERS AND THUNDERSTORMS OVER LA HISPANIOLA. MOST OF THE CONVECTIVE ACTIVITY IS OVER HAITI AND W OF 70W OVER THE DOMINICAN REPUBLIC. AN UPPER LEVEL SHORT-WAVE TROUGH IS ALSO EAST OF THE ISLAND DRAWING MOIST AIR ALOFT FROM THE DEEP LAYER MOISTURE OVER THE WESTERN CARIBBEAN AND WEST ATLC. RAINSHOWERS ARE EXPECTED TO CONTINUE WITHIN THE NEXT 24 HOURS SUPPORTED BY A SIMILAR UPPER LEVEL SYNOPTIC PATTERN AND SURFACE MOISTURE. ATLANTIC OCEAN... SURFACE RIDGING IS THE DOMINANT SURFACE FEATURE ACROSS THE ATLC N OF 17N. HOWEVER...DEEP LAYER MOISTURE COVERS THE W ATLC INCLUDING THE BAHAMAS. THIS MOISTURE ALONG WITH A MIDDLE TO UPPER LEVEL TROUGH EXTENDING SW FROM A LOW NEAR 33N68W ARE SUPPORTING NUMEROUS SHOWERS AND THUNDERSTORMS S OF 28N W OF 67W. ABUNDANT MOISTURE IS EXPECTED TO REMAIN OVER THIS AREA FOR THE NEXT 24 HOURS INCREASING THE CHANCES OF RAINSHOWERS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR