000 AXNT20 KNHC 261040 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT WED JUN 26 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS CROSSING EASTERN CUBA WITH AXIS EXTENDING FROM 21N75W TO 15N78W. THIS WAVE IS MOVING W-NW AT 10 KT IN THE SW PERIPHERY OF A BROAD SURFACE RIDGE COVERING THE ATLC...PORTIONS OF THE CARIBBEAN AND THE GULF. THE WAVE IS WITHIN AN ENVIRONMENT OF MODERATE MOISTURE IN THE LOWER AND MIDDLE LEVELS N OF 17N WHICH IS ENHANCING ISOLATED SHOWERS AND THUNDERSTORMS OVER CUBA AS WELL AS WITHIN 60 NM OF THE ISLAND SE COAST. THE WAVE WILL CONTINUE A WESTWARD TRACK AND IS EXPECTED TO VANISH BEFORE/AFTER CROSSING WESTERN CUBA TODAY IN THE AFTERNOON. TROPICAL WAVE AXIS CROSSING EASTERN PUERTO RICO IS ENHANCING SCATTERED SHOWERS OVER THE ISLAND AND ADJACENT WATERS. ITS AXIS EXTENDS FROM 19N65W TO 12N66W AND IS MOVING W-NW AT 5 KT. CONTINUOUS RAINSHOWERS ASSOCIATED WITH IT MAY LEAD TO ACCUMULATIONS OF TWO INCHES OR MORE IN SOME AREAS OF THE ISLAND. THE WAVE IS EMBEDDED IN AN ENVIRONMENT OF MODERATE MOISTURE IN THE LOWER AND MIDDLE LEVELS WITH TRAILING HIGH MOISTURE ALONG THE LESSER ANTILLES WHERE THUNDERSTORM ACTIVITY HAS BEEN REPORTED. THE WAVE AXIS IS EXPECTED TO BE CROSSING THE MONA PASSAGE EARLY THIS EVENING. RAINSHOWERS WILL CONTINUE ACROSS THE ISLAND DURING THAT PERIOD WITH SKIES CLEARING VERY EARLY ON THURSDAY. TROPICAL WAVE CONTINUE EMBEDDED WITHIN THE ITCZ WITH AXIS ALONG 12N39W TO 02N39W...MOVING WEST AT 10 KT. IT IS SHOWING A BETTER AMPLITUDE IN THE 700 MB AND CLUSTERS OF MODERATE CONVECTION ASSOCIATED TO THIS WAVE AND THE ITCZ AXIS ARE FROM 03N-07N BETWEEN 41W-49W WHERE HIGH LOWER AND MIDDLE LEVELS HUMIDITY IS OBSERVED IN TOTAL PRECIPITABLE WATER AND WATER VAPOR IMAGERY. NO CONVECTION IS OCCURRING IN THE NORTHERN ENVIRONMENT OF THE WAVE N OF 07N DUE TO THE PRESENCE OF SAHARAN DRY AIR. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL WEST AFRICA NEAR 10N14W TO 08N21W. THE ITCZ STARTS NEAR 08N21W AND IT CONTINUES TO 07N29W 06N37W. BESIDES THE CONVECTION ALREADY DESCRIBED ABOVE ASSOCIATED WITH THE TROPICAL WAVE EMBEDDED IN THE ITCZ...CLUSTERS OF STRONG CONVECTION ARE FROM 07N-11N EAST OF 21W. ...DISCUSSION... THE GULF OF MEXICO... BROAD SURFACE RIDGING FROM A SET OF HIGH PRESSURES OVER THE NORTH ATLC EXTENDS INTO THE GULF GENERATING RETURN FLOW IN THE RANGE OF 10-15 KT ACROSS MOST OF THE BASIN WITH A MAXIMUM OF 20 KT IN THE NW GULF. AN UPPER LEVEL CYCLONIC CIRCULATION OVER THE YUCATAN PENINSULA IS SUPPORTING A SURFACE TROUGH ACROSS THE BAY OF CAMPECHE FROM 21N89W TO 18N93W. ISOLATED SHOWERS/THUNDERSTORMS ARE OCCURRING WITHIN 60 NM EAST OF THE AXIS. SIMILAR CONVECTION IS OCCURRING OVER THE SE GULF JUST NW OF KEY WEST AND IS BEING ENHANCED BY UPPER LEVEL DIFFLUENT FLOW FROM A RIDGE AXIS CENTERED OVER FLORIDA AND THE BROAD RIDGE THAT SPREADS OVER THE CARIBBEAN. TOTAL PRECIPITABLE WATER AND WATER VAPOR IMAGERY SHOW A DRY ENVIRONMENT IN THE LOWER AND MIDDLE LEVELS W OF 91W N OF 20N WHICH IS SUPPRESSING ANY TYPE OF CONVECTIVE ACTIVITY. NO SIGNIFICANT CHANGES ARE EXPECTED DURING THE NEXT 48 HOURS AS THE CURRENT WEATHER FEATURES IN THE LOWER AND UPPER LEVELS ARE EXPECTED TO PREVAIL. THE CARIBBEAN SEA... TROPICAL WAVE IS CROSSING EASTERN CUBA WITH AXIS EXTENDING FROM 21N75W TO 15N78W. TROPICAL WAVE IS CROSSING EASTERN CUBA WITH AXIS EXTENDING FROM 21N75W TO 15N78W. A TROPICAL WAVE AXIS IS CROSSING EASTERN PUERTO RICO AND IS ENHANCING SCATTERED SHOWERS OVER THE ISLAND AND ITS ADJACENT WATERS. CONTINUOUS RAINSHOWERS ASSOCIATED WITH IT MAY LEAD TO ACCUMULATIONS OF TWO INCHES OR MORE IN SOME AREAS OF THE ISLAND. THE WAVE IS EMBEDDED IN AN ENVIRONMENT OF MODERATE MOISTURE IN THE LOWER AND MIDDLE LEVELS WITH TRAILING HIGH MOISTURE ALONG THE LESSER ANTILLES WHERE THUNDERSTORM ACTIVITY HAS BEEN REPORTED. ISOLATED MODERATE CONVECTION IS OCCURRING OVER THE SOUTHERN CARIBBEAN S OF 11N WHERE HIGH MOISTURE IS OBSERVED AT THE LOWER LEVELS. ISOLATED SHOWERS/THUNDERSTORMS ARE OCCURRING EAST OF THE YUCATAN PENINSULA AND BELIZE DUE TO BANKING OF LOW LEVEL CLOUDS BY THE TRADEWINDS. ELSEWHERE CLEAR SKIES ARE BEING SUPPORTED BY THE PRESENCE OF DRY AIR IN THE LOWER LEVELS. IN THE UPPER LEVELS A BROAD RIDGE COVERS THE BASIN WHILE AT THE SURFACE TRADEWINDS IN THE RANGE OF 10-15 KT DOMINATE. OTHERWISE...THE WAVE OVER EASTERN CUBA WILL CONTINUE A WESTWARD TRACK AND IS EXPECTED TO VANISH BEFORE/AFTER CROSSING THE WEST SIDE OF THE ISLAND TODAY IN THE AFTERNOON. THE WAVE AXIS IS EXPECTED TO BE CROSSING THE MONA PASSAGE EARLY THIS EVENING. RAINSHOWERS WILL CONTINUE ACROSS THE ISLAND DURING THAT PERIOD WITH SKIES CLEARING VERY EARLY ON THURSDAY. HISPANIOLA... DRY SURFACE CONDITIONS ARE ACROSS THE ISLAND WHILE LIGHT TRADEWINDS OF 5-10 KT FLOW OVER IT. FAIR WEATHER IS EXPECTED TO CONTINUE UNTIL THIS MORNING. HOWEVER WEATHER CONDITIONS WILL START TO DEGRADE IN THE AFTERNOON AS THE TROPICAL WAVE MOVING ACROSS PUERTO RICO CONTINUES TO MOVE WESTWARD PUSHING AN ENVELOPE OF MOISTURE AHEAD OF IT. THE AXIS OF THIS WAVE IS EXPECTED TO ENTER THE DOMINICAN REPUBLIC EARLY IN THE EVENING TODAY. RAINSHOWERS WITH ACCUMULATIONS OF TWO INCHES OR HIGHER CAN BE EXPECTED. THE AXIS OF THIS WAVE IS EXPECTED TO BE OVER THE WINDWARD PASSAGE ON THURSDAY AFTERNOON. THE ATLANTIC OCEAN... BROAD SURFACE RIDGING DOMINATES ACROSS THE BASIN N OF 16N FROM A SET OF HIGH PRESSURE CENTERS N OF THE AREA OF DISCUSSION AND A 1021 MB NEARLY STATIONARY HIGH NEAR 30N63W. MODERATE MOISTURE AT THE LOWER LEVELS AND UPPER LEVEL DIFFLUENCE ARE ENHANCING AN AREA OF SHOWERS AND THUNDERSTORMS SW OF THE HIGH FROM 24N-27N BETWEEN 64W-68W. EXCEPT FOR THE AREAS DISCUSSED ABOVE...TOTAL PRECIPITABLE WATER IMAGERY SHOW AN OVERALL DRY ENVIRONMENT AT THE LOWER LEVELS WHICH IS SUPPORTING FAIR WEATHER BASIN WIDE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ RAMOS