000 AXNT20 KNHC 210603 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN JUN 21 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0545 UTC. ...SPECIAL FEATURES... A TIGHT PRESSURE GRADIENT BETWEEN STRONG HIGH PRES N OF THE AREA AND LOW PRESSURE OVER THE SW CARIBBEAN ASSOCIATED WITH A TROPICAL WAVE AND A LOW OVER NORTHERN COLOMBIA IS SUPPORTING PULSES OF GALE FORCE WINDS ALONG THE COAST OF COLOMBIA AND IN THE GULF OF VENEZUELA...EXPECTED TO CONTINUE OVER THE NEXT COUPLE OF DAYS. WINDS TO GALE FORCE CAN BE EXPECTED PRIMARILY AT NIGHT AND IN THE EARLY MORNING HOURS...BUT STRONG TO NEAR GALE FORCE WINDS WILL PERSIST THROUGHOUT THE DAY AND NIGHT ACROSS MUCH OF THE CENTRAL CARIBBEAN INTO SUNDAY. THE WINDS WILL DIMINISH SLIGHTLY MONDAY AS THE NEXT TROPICAL WAVE MOVES INTO THE AREA...BUT INCREASE AGAIN BY MID WEEK. PLEASE READ THE HIGH SEAS FORECAST... MIAHSFAT2/FZNT02 KNHC...AND THE OFFSHORE FORECAST...MIAOFFNT3/ FZNT23 KNHC...FOR MORE DETAILS. ...TROPICAL WAVES... A TROPICAL WAVE CAME OFF THE WEST AFRICAN COAST SATURDAY NIGHT. THE WAVE AXIS IS APPROXIMATELY LOCATED AT 17W MOVING W AT 10 KT. SSMI TPW IMAGERY INDICATE THE WAVE IS EMBEDDED IN A MODERATE MOIST ENVIRONMENT WHILE METEOSAT IMAGERY SHOW SAHARAN DUST AND DRY AIR ENGULFING THE NORTHERN REGION OF IT. SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS ARE FROM 10N TO 12N BETWEEN 15W AND 18W. A TROPICAL WAVE IS OVER THE CENTRAL TROPICAL ATLC WITH AXIS NEAR 35W MOVING W AT 15 KT OVER THE PAST 24 HOURS. THE TOTAL PRECIPITABLE WATER IMAGERY SHOW THE WAVE IS EMBEDDED IN A MODERATE MOIST ENVIRONMENT EXCEPT IN THE NORTHERN REGION WHERE METEOSAT SATELLITE IMAGERY DEPICT SAHARAN DRY AIR AND DUST. NO CONVECTION IS ASSOCIATED WITH THE WAVE AT THIS TIME. A TROPICAL WAVE IS IN THE WESTERN TROPICAL ATLC WITH AXIS ALONG 53W MOVING W NEAR 15 KT OVER THE PAST 24 HOURS. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS MAINLY EMBEDDED WITHIN A MODERATE MOIST ENVIRONMENT EXCEPT FROM 10N TO 13N BETWEEN 48W AND 57W WHERE ABUNDANT MOISTURE SUPPORTS SCATTERED MODERATE CONVECTION. A TROPICAL WAVE IS IN THE SW CARIBBEAN BASIN WITH AXIS ALONG 80W FROM 17N TO PANAMA MOVING W NEAR 10 KT OVER THE PAST 24 HOURS. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS MAINLY EMBEDDED WITHIN AN AREA OF RELATIVELY DRY AIR THAT IS HINDERING DEEP CONVECTION N OF 12N. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS AHEAD OF THE WAVE AXIS S OF 12N...INCLUDING COSTA RICA AND NORTHERN PANAMA. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE TROPICAL ATLC NEAR 09N13W AND CONTINUES TO 07N24W TO 07N33W. THE ITCZ BEGINS NEAR 08N36W AND CONTINUES TO E OF A TROPICAL WAVE NEAR 07N52W. BESIDES THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVES...SCATTERED MODERATE CONVECTION IS FROM 04N TO 09N BETWEEN 19W AND 31W. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER LOW REMAINS ANCHORED OVER THE NW YUCATAN PENINSULA ENHANCING A FEW SHOWERS OFF THE NORTHERN COAST OF YUCATAN INTO THE CENTRAL GULF. SCATTERED MODERATE CONVECTION IS OVER THE WEST CENTRAL AND SOUTHWEST FLORIDA EXTENDING WITHIN 60 NM OFF THE COAST BEING SUPPORTED BY MOISTURE INFLOW FROM THE CARIBBEAN AND MIDDLE LEVEL DIFFLUENCE. ISOLATED SHOWERS AND TSTMS ARE OFF THE NE COAST OF MEXICO FROM 22N TO 24N. OTHERWISE GENERALLY FAIR SKIES PREVAIL ACROSS THE GULF DUE TO THE SUBSIDENCE AROUND THE UPPER LOW. SCATTEROMETER DATA INDICATE E TO SE WINDS OF 10 TO 15 KT OVER THE SE GULF AND AHEAD OF A SURFACE TROUGH OVER THE BAY OF CAMPECHE FROM 22N90W TO 16N93W. VARIABLE WINDS OF 5 KT CONTINUE TO DOMINATE THE NE BASIN AROUND HIGH PRES CENTERED NEAR 27N86W. NO MAJOR CHANGES ARE EXPECTED IN THE WEATHER PATTERN OVER THE NEXT SEVERAL DAYS. THE CARIBBEAN SEA... A TIGHT PRESSURE GRADIENT BETWEEN STRONG HIGH PRES N OF THE AREA AND LOW PRESSURE OVER THE SW CARIBBEAN ASSOCIATED WITH A TROPICAL WAVE ALONG 80W AND A LOW OVER NORTHERN COLOMBIA IS SUPPORTING PULSES OF GALE FORCE WINDS ALONG THE COAST OF COLOMBIA AND IN THE GULF OF VENEZUELA...EXPECTED TO CONTINUE OVER THE NEXT COUPLE OF DAYS. SEE THE SPECIAL FEATURES AND TROPICAL WAVES SECTIONS FOR MORE DETAILS. A DIFFLUENT ENVIRONMENT BETWEEN AN UPPER LOW CENTERED OVER THE NW YUCATAN PENINSULA AND A RIDGE COVERING PORTIONS OF THE NW AND SW CARIBBEAN ALONG WITH SHALLOW MOISTURE SUPPORT SCATTERED SHOWERS AND TSTMS WITHIN 60 NM OFF THE SOUTHERN COAST OF CUBA. A SECOND UPPER LOW IS CENTERED OVER NE OF THE LEEWARD ISLANDS...HOWEVER WITH DRY AIR AROUND IT...THUS HINDERING THE DEVELOPMENT OF CONVECTION. OTHERWISE...SAHARAN DRY AIR AND DUST CONTINUES TO SUPPORT HAZY CONDITIONS ACROSS THE EASTERN BASIN...INCLUDING THE LESSER ANTILLES. THE NEXT TROPICAL WAVE ENTERS THE EASTERN CARIBBEAN TUESDAY MORNING. ...HISPANIOLA... SHALLOW MOISTURE MOVED ACROSS HISPANIOLA LEAVING SCATTERED CLOUDS OVER SW DOMINICAN REPUBLIC AND S HAITI ADJACENT WATERS. METEOSAT SATELLITE IMAGERY INDICATE THE PRESENCE OF SAHARAN DUST AND DRY AIR ACROSS THE ISLAND...WHICH IS SUPPORTING HAZE IN SOME REGIONS. WATER VAPOR IMAGERY ALSO DEPICT DRY AIR ALOFT. EXCEPT FOR THE TYPICAL AFTERNOON SHOWERS...FAIR WEATHER IS EXPECTED THROUGH THE REST OF THE WEEKEND. THE ATLANTIC OCEAN... BROAD SURFACE RIDGING COVERS THE ATLC BEING ANCHORED BY A 1027 MB HIGH NEAR 31N35W. METEOSAT SATELLITE IMAGERY INDICATE SAHARAN DRY AIR AND DUST COVERING MOST OF THE TROPICS S OF 20N...THUS LIMITING SHOWER ACTIVITY. FOR INFORMATION ON TROPICAL WAVES SEE SECTION ABOVE. SURFACE RIDGING WILL BE THE DOMINANT FEATURE THE NEXT THREE DAYS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR