000 AXNT20 KNHC 151046 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT AUG 15 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS IN THE E ATLC ASSOCIATED WITH A 1011 MB LOW NEAR 10N20W. CIRA LAYER PRECIPITABLE WATER IMAGERY FROM THE SURFACE TO 850 MB SHOW THE WAVE IS ASSOCIATED WITH A BROAD AREA OF MODERATE MOISTURE THAT ALONG WITH A DIFFLUENT WIND ENVIRONMENT ALOFT SUPPORT SCATTERED TO ISOLATED SHOWERS AND TSTMS FROM 05N TO 13N E OF 24W. A TROPICAL WAVE IS IN THE CENTRAL ATLC WITH AXIS NEAR 42W ...MOVING W AT 10 KT OVER THE PAST 24 HOURS. CIRA LAYER PRECIPITABLE WATER IMAGERY FROM THE SURFACE TO 850 MB SHOW THE WAVE IS WITHIN A DRY ENVIRONMENT...WHICH IS KEEPING THE WAVE DEVOID OF CONVECTION. A TROPICAL WAVE ENTERED THE EASTERN CARIBBEAN. ITS AXIS IS NEAR 63W AND HAS BEEN MOVING W AT 15 KT OVER THE PAST 24 HOURS. THE WAVE IS ASSOCIATED WITH A MODERATE MOIST ENVIRONMENT FROM THE SURFACE TO 850 MB ACCORDING TO CIRA LAYER PRECIPITABLE WATER IMAGERY. A DIFFLUENT WIND ENVIRONMENT AT THE UPPER LEVELS IN THE NE CARIBBEAN AND ADJACENT ATLC WATERS ALONG WITH THE MOISTURE SUPPORT SCATTERED TO ISOLATED SHOWERS OVER PUERTO RICO...VIRGIN ISLANDS AND NORTHERN LEEWARD ISLANDS. STRONG DEEP LAYER WIND SHEAR HINDER CONVECTION ACROSS THE E-SE CARIBBEAN BASIN. A TROPICAL WAVE EXTENDS FROM THE YUCATAN PENINSULA...ACROSS GUATEMALA TO EPAC WATERS. ITS AXIS IS NEAR 91W AND HAS BEEN MOVING AT 5 KT OVER THE LAST 24 HOURS. THE WAVE IS ASSOCIATED WITH A MODERATE MOIST ENVIRONMENT FROM THE SURFACE TO 850 MB ACCORDING TO CIRA LAYER PRECIPITABLE WATER IMAGERY. SCATTERED TO ISOLATED SHOWERS AND TSTMS ARE OVER THE NW CARIBBEAN W OF 81W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 11N15W TO A 1011 MB LOW NEAR 10N20W TO 08N29W WHERE THE ITCZ CONTINUES TO 06N44W TO 08N53W TO GUYANA COASTLINE NEAR 08N59W. OTHER THAN THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVE NEAR THE CAPE VERDE ISLANDS...SCATTERED MODERATE CONVECTION IS FROM 06N TO 11N BETWEEN 37W AND 42W. ISOLATED SHOWERS ARE WITHIN 75 NM EITHER SIDE OF THE ITCZ W OF 43W. ...DISCUSSION... ...GULF OF MEXICO... A SURFACE TROUGH EXTENDS ACROSS NORTHERN FLORIDA SW TO 29N90W TO 28N96W WITH ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF ITS AXIS. A SECOND SURFACE TROUGH IS ANALYZED FROM 27N86W TO 25N90W TO 22N93W BEING SUPPORTED BY A MIDDLE TO UPPER LEVEL TROUGH OVER THE EASTERN CONUS WITH BASE EXTENDING INTO THE E GULF. LOW LEVEL MOISTURE INFLOW FROM THE CARIBBEAN TO THE GULF ALONG WITH A DIFFLUENT ENVIRONMENT BETWEEN THE BASE OF THE UPPER TROUGH AND AN UPPER HIGH NEAR 23N85W SUPPORT SCATTERED SHOWERS AND TSTMS OVER THE SE GULF AHEAD OF THE TROUGH FROM 23N TO 27N E OF 89W. EASTERLY WIND FLOW OF 15 KT IS OVER THE NE GULF N OF 28N... VARIABLE WINDS OF LESS THAN 15 KT DOMINATE ELSEWHERE. SURFACE TROUGHING WILL PREVAIL ACROSS THE NORTHERN GULF THROUGH TONIGHT. SURFACE RIDGING WILL START TO BUILD ACROSS THE ENTIRE BASIN SUNDAY. CARIBBEAN SEA... A TROPICAL WAVE IS MOVING ALONG THE YUCATAN PENINSULA...GUATEMALA TO EPAC WATERS. THE WAVE IS ASSOCIATED WITH SHALLOW MOISTURE THAT ENHANCE ISOLATED SHOWERS AND TSTMS OVER THE NW CARIBBEAN W OF 84W. A SECOND TROPICAL WAVE ENTERED THE EASTERN BASIN EARLIER THIS MORNING. THE WAVE IS ASSOCIATED WITH A MODERATE MOIST ENVIRONMENT AT THE LOWER LEVELS THAT ALONG WITH A DIFFLUENT WIND ENVIRONMENT AT THE UPPER LEVELS IN THE NE CARIBBEAN SUPPORT SCATTERED TO ISOLATED SHOWERS OVER PUERTO RICO...VIRGIN ISLANDS AND NORTHERN LEEWARD ISLANDS. STRONG DEEP LAYER WIND SHEAR HINDER CONVECTION ACROSS THE CENTRAL AND REMAINDER E CARIBBEAN BASIN. SEE TROPICAL WAVES SECTION FOR MORE DETAILS. DIFFLUENCE ALOFT BETWEEN AN UPPER RIDGE OVER THE SW N ATLC AND A BROAD RIDGE CENTERED OVER THE SE CARIBBEAN SUPPORT SCATTERED TO ISOLATED SHOWERS ACROSS THE WINDWARD PASSAGE. LOW PRESSURE OVER NW COLOMBIA ENHANCES SCATTERED MODERATE CONVECTION AND TSTMS S OF 12N E OF 82W. NE TO E WINDS OF 20 TO 25 KT ARE FROM 11N TO 14N BETWEEN 71W AND 76W WITH SEAS TO 9 FT. THE WAVE OVER THE E BASIN WILL MOVE OVER PUERTO RICO SATURDAY ENHANCING SHOWERS AND OVER THE CENTRAL BASIN SUNDAY THROUGH MONDAY ENHANCING SHOWERS ACROSS HISPANIOLA. ...HISPANIOLA... SHALLOW MOISTURE ACROSS THE CARIBBEAN SEA ALONG WITH A DIFFLUENT REGION ALOFT BETWEEN AN UPPER RIDGE OVER THE SW N ATLC AND A BROAD RIDGE CENTERED OVER THE SE CARIBBEAN SUPPORT SCATTERED SHOWERS ACROSS THE WINDWARD PASSAGE AND ISOLATED SHOWERS OVER THE ISLAND. SHOWERS ARE FORECAST TO CEASE THIS AFTERNOON. HOWEVER...THE PASSAGE OF A TROPICAL WAVE DURING SUNDAY AND MONDAY WILL BRING SHOWERS THAT ARE FORECAST TO PERSIST THROUGH EARLY TUESDAY MORNING. ATLANTIC OCEAN... A DISSIPATING STATIONARY FRONT EXTENDS FROM 30N80W TO JACKSONVILLE WHERE IT TRANSITIONS INTO A SURFACE TROUGH THAT EXTENDS ACROSS NORTHERN FLORIDA. THE TROUGH IS BEING SUPPORTED BY A MIDDLE TO UPPER LEVEL TROUGH OVER THE E CONUS AND FAR W-NW ATLC. ISOLATED SHOWERS AND TSTMS CONTINUE BETWEEN THE SOUTHERN FLORIDA PENINSULA AND THE NORTHERN-CENTRAL BAHAMAS. A BROAD SURFACE RIDGE COVERS THE REMAINDER BASIN AND SUPPORTS FAIR WEATHER. FOR TROPICAL WAVES SEE SECTION ABOVE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR