000 AXNT20 KNHC 301805 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE JUN 30 2015 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...SPECIAL FEATURES... GALE-FORCE WINDS CONTINUES ALONG THE COASTAL WATERS OF COLOMBIA FROM 11.5N TO 13N BETWEEN 74W AND 77W WITH ASSOCIATED SEAS RANGING FROM 10 TO 15 FT. WINDS WILL DIMINISH BELOW GALE-FORCE THIS AFTERNOON...HOWEVER RESUMING TONIGHT. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...AND THE OFFSHORE FORECAST...MIAOFFNT3/FZNT23 KNHC...FOR MORE DETAILS. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER THE CENTRAL TROPICAL ATLC WITH AXIS NEAR 29W FROM 04N TO 12N...MOVING W AT 15-20 KT. METEOSAT AIRMASS...SAL TRACKING AND PSEUDO-NATURAL COLOR IMAGERY DEPICT SAHARAN DRY AIR AND DUST IN THE NORTHERN WAVE ENVIRONMENT. THE SOUTHERN PORTION OF THE WAVE IS EMBEDDED IN THE ITCZ WHERE ABUNDANT MOISTURE SUPPORT SCATTERED MODERATE CONVECTION FROM 06N TO 08N BETWEEN 25W AND 34W. A TROPICAL WAVE IS E OF THE LESSER ANTILLES WITH AXIS NEAR 59W...MOVING W AT 15-20 KT. SSMI TPW IMAGERY SHOW THE WAVE IS EMBEDDED IN AN ABUNDANT MOIST ENVIRONMENT THAT ALONG WITH A DIFFLUENT ENVIRONMENT ALOFT SUPPORT SCATTERED MODERATE CONVECTION FROM 10N TO 13N BETWEEN 57W AND 64W AND ISOLATED SHOWERS FROM 13N TO 17N BETWEEN 55W AND 64W. A TROPICAL WAVE IS OVER THE EASTERN CARIBBEAN WITH AXIS NEAR 66W...MOVING W AT 15 KT. SSMI TPW IMAGERY SHOW THE WAVE IS MAINLY EMBEDDED IN A DRY ENVIRONMENT...EXCEPT N OF 16N WHERE A PATCH OF MODERATE MOISTURE ENHANCES SCATTERED TO ISOLATED SHOWERS AND TSTMS OVER PUERTO RICO AND ADJACENT WATERS AND THE U.S. VIRGIN ISLANDS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH COASTAL SECTIONS OF GUINEA- BISSAU NEAR 11N15W TO 09N21W. THE ITCZ BEGINS NEAR 09N21W AND CONTINUES TO 08N28W...RESUMING NEAR 07N31W THEN CONTINUING ALONG 05N41W TO 06N49W TO 08N56W. ASIDE THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVES...SCATTERED MODERATE CONVECTION IS FROM 07N TO 10N E OF 25W AND WITHIN 75 NM EITHER SIDE OF THE ITCZ BETWEEN 35W AND 50W. ...DISCUSSION... GULF OF MEXICO... THE NORTHERN PERIPHERY OF AN ELONGATED UPPER RIDGE ANCHORED OVER THE EPAC WATERS SW OF GUATEMALA COVERS THE WESTERN GULF S OF 26N. N OF 26N THE BASE OF AN UPPER TROUGH EXTENDING ACROSS THE EASTERN CONUS GENERATES A DIFFLUENT ENVIRONMENT THAT ALONG WITH ABUNDANT MOISTURE BEING ADVECTED FROM THE CARIBBEAN SUPPORT SCATTERED MODERATE CONVECTION AND TSTMS FROM 21N TO 27N W OF 91W AND N OF 28N BETWEEN SW LOUISIANA AND GALVESTON TEXAS. MAINLY DRY AIR COVERS THE EASTERN BASIN...EXCEPT FOR SOME PATCHES OF MODERATE MOIST AIR THAT ALONG WITH AN UPPER-LEVEL LOW CENTERED NEAR 26N84W SUPPORT SCATTERED CLOUDS WITH POSSIBLE ISOLATED SHOWERS OVER THE SE GULF E OF 85W...INCLUDING THE STRAITS OF FLORIDA. OTHERWISE...SURFACE HIGH PRESSURE AND RIDGING DOMINATE ACROSS THE BASIN BEING ANCHORED BY A 1021 MB HIGH NEAR 26N84W. EXCEPT FOR SURFACE TROUGHING IN THE BAY OF CAMPECHE...SURFACE HIGH PRESSURE AND RIDGING WILL DOMINATE ACROSS THE BASIN THE NEXT TWO DAYS. CARIBBEAN SEA... GALE-FORCE WINDS CONTINUES ALONG COLOMBIA COASTAL WATERS THROUGH THIS AFTERNOON. FOR MORE INFORMATION SEE SPECIAL FEATURES. A TROPICAL WAVE IS MOVING ACROSS THE EASTERN CARIBBEAN WITH AXIS JUST EAST OF PUERTO RICO. AN UPPER LEVEL LOW AHEAD OF THE WAVE CENTERED N OF HISPANIOLA ALONG WITH A PATCH OF MODERATE MOISTURE SUPPORT SCATTERED TO ISOLATED MODERATE CONVECTION AND TSTMS ACROSS PUERTO RICO AND N-NW ADJACENT WATERS. ANOTHER TROPICAL WAVE APPROACHES THE LESSER ANTILLES ASSOCIATED WITH A BULGE OF MOISTURE THAT CURRENTLY ENHANCES SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS OVER THE SE CARIBBEAN S OF 15N E OF 65W. SEE TROPICAL WAVES SECTION ABOVE FOR MORE DETAILS. A 1010 MB LOW IS JUST OFF THE COAST OF NW COLOMBIA NEAR 9N76W THUS ENHANCING SCATTERED TO ISOLATED SHOWERS S OF 13N. SIMILAR CONVECTION IS OVER NORTHERN HISPANIOLA ALONG WITH TSTMS BEING SUPPORTED BY THE UPPER LEVEL LOW AND A MIDDLE LEVEL INVERTED TROUGH. ELSEWHERE DEEP LAYER DRY AIR DOMINATES...THUS SUPPORTING FAIR WEATHER. THE TWO TROPICAL WAVES WILL BE THE MAIN FEATURE ACROSS THE BASIN DURING THE NEXT TWO DAYS. ...HISPANIOLA... AN UPPER-LEVEL LOW IS CENTERED JUST N OF HISPANIOLA THAT ALONG WITH A MODERATE MOIST AIRMASS SUPPORT SCATTERED TO ISOLATED SHOWERS AND TSTMS MAINLY ACROSS THE NORTHERN DOMINICAN REPUBLIC AND ADJACENT WATERS. A TROPICAL WAVE WILL BE MOVING ACROSS THE CENTRAL BASIN WED ASSOCIATED WITH A MODERATE AIRMASS IN ITS NORTHERN ENVIRONMENT THAT WILL ENHANCE SHOWERS ACROSS THE ISLAND DURING THE DAY. ATLANTIC OCEAN... A MIDDLE-LEVEL TROUGH CONTINUES ACROSS THE SW N ATLC WATERS THUS SUPPORTING SCATTERED TO ISOLATED MODERATE CONVECTION AND TSTMS N OF 25N BETWEEN 71W AND 80W. SIMILAR CONVECTION IS ON THE DOMINICAN REPUBLIC AND PUERTO RICO NORTHERN OFFSHORE WATERS. AN UPPER TROUGH OVER THE E PAC CONTINUE TO SUPPORT A DISSIPATING COLD FRONT THAT EXTENDS FROM 29N33W TO 28N46W TO 27N55W. RIDGING AND HIGH PRESSURE DOMINATES ELSEWHERE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR