000 AXNT20 KNHC 100552 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT WED JUL 10 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...SPECIAL FEATURES... TROPICAL STORM CHANTAL IS CENTERED NEAR 15.5N 68.0W AT 10/0600 UTC OR ABOUT 205 NM SSW OF SAN JUAN PUERTO RICO AND ABOUT 200 NM SSE OF SANTO DOMINGO DOMINICAN REPUBLIC MOVING W AT 26 KT. ESTIMATED MIMIMUM CENTRAL PRESSURE IS 1011 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. SCATTERED MODERATE CONVECTION IS FROM 13N-16N BETWEEN 63W-67W. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT3/WTNT33 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 07N21W TO 16N20W MOVING W AT 10-15 KT. THE WAVE REMAINS EMBEDDED WITHIN THE MONSOON TROUGH/ITCZ AXIS AND COINCIDES WITH A GLOBAL MODEL INDICATED 700 MB TROUGH AND ASSOCIATED VORTICITY MAXIMUM IN THE VICINITY OF 12N21W. TOTAL PRECIPITABLE WATER IMAGERY SHOWS A RELATIVE MOISTURE MAXIMUM FROM 09N-15N BETWEEN 18W-26W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 08N-14N BETWEEN 18W-24W. TROPICAL WAVE EXTENDS FROM 03N40W TO 11N34W MOVING W AT 5-10 KT. THE WAVE REMAINS EMBEDDED WITHIN THE ITCZ AXIS S OF 10N WITH LOW- LEVEL STREAMLINE ANALYSIS INDICATING CYCLONIC TURNING VERTICALLY THROUGH 700 MB S OF 12N BETWEEN 30W-40W. A SAHARAN AIR LAYER REMAINS ON THE NORTHERN PERIPHERY OF THE WAVE AXIS AND THIS IS RESULTING IN VERY LIMITED CONVECTION AT THIS TIME. WIDELY SCATTERED MODERATE CONVECTION LARGELY REMAINS E OF 35W AND ASSOCIATED WITH THE ITCZ AXIS. TROPICAL WAVE EXTENDS FROM 16N91W TO 22N90W MOVING W AT 10-15 KT. THE WAVE...LARGELY INLAND ACROSS PORTIONS OF SOUTHERN MEXICO AND NORTHERN GUATEMALA CONTINUES TO BECOME MORE DIFFUSE AND MORE DIFFICULT TO TRACK. HOWEVER...WIDELY SCATTERED MODERATE CONVECTION IS OCCURRING THIS EVENING FROM 15N-20N BETWEEN 88W- 93W. GLOBAL MODEL DATA INDICATES ANY REMNANTS OF THIS WAVE WILL LIKELY MOVE ACROSS PORTIONS OF SOUTHERN MEXICO AND THE NEAR COASTAL EASTERN PACIFIC WATERS THROUGH LATE WEDNESDAY. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 13N17W TO 12N21W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 12N21W TO 07N37W TO 04N43W TO THE EQUATOR NEAR 48W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM NORTH AND 210 NM SOUTH OF THE AXIS BETWEEN 23W-34W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY INDICATES NORTHERLY UPPER LEVEL FLOW DOMINATES OVER THE GULF BETWEEN A MIDDLE TO UPPER LEVEL ANTIYCYCLONIC CIRCULATION CENTERED OVER THE TEXAS PANHANDLE NEAR 35N102W AND AN UPPER LEVEL LOW CENTERED OVER THE FLORIDA STRAITS NEAR 25N80W. MOSTLY DRY AIR ALOFT PREVAILS AND ALONG WITH A SURFACE RIDGE ANCHORED BY A 1020 MB HIGH CENTERED NEAR 28N88W THE BASIN REMAINS UNDER FAIRLY QUIET CONDITIONS THIS EVENING. AS THE UPPER LEVEL LOW DRIFTS W-NW...INCREASING CLOUDS AND MOISTURE ARE NOTED OVER THE SOUTHERN FLORIDA PENINSULA AND FAR EASTERN GULF WITH ISOLATED SHOWERS OCCURRING S OF 28N E OF 84W. ISOLATED SHOWERS ARE ALSO OCCURRING OVER THE WESTERN GULF S OF 28N W OF 93W. SURFACE RIDGING IS FORECAST TO HOLD FAIRLY STATIONARY OVER THE BASIN THROUGH LATE THURSDAY AS TROPICAL STORM CHANTAL... CURRENTLY CENTERED OVER THE EASTERN CARIBBEAN SEA...IS EXPECTED TO BE POSITIONED IN THE EASTERN FLORIDA STRAITS AND MOST LIKELY BE IMPACTING PORTIONS OF THE SE GULF AND SOUTHERN FLORIDA PENINSULA WITH PRECIPITATION INTO THE UPCOMING WEEKEND. CARIBBEAN SEA... THE PRIMARY FOCUS FOR THE CARIBBEAN IS TROPICAL STORM CHANTAL WHICH IS POSITIONED IN THE EASTERN CARIBBEAN AND PROVIDING SCATTERED SHOWERS AND WIDELY SCATTERED TSTMS E OF 69W... INCLUDING PUERTO RICO AND MANY OF THE LESSER ANTILLES. CHANTAL IS FORECAST TO TRACK W-NW OVER THE NEXT 24 HOURS AND BEGIN IMPACTING HISPANIOLA DURING THE DAY ON WEDNESDAY. OTHERWISE...AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER HONDURAS NEAR 15N88W AND IS PROVIDING MUCH OF THE WESTERN CARIBBEAN WITH NW TO NORTHERLY FLOW ALOFT. WHILE THE CENTRAL CARIBBEAN BETWEEN 70W-80W REMAINS FAIRLY TRANQUIL THIS EVENING...UPPER LEVEL DIFFLUENCE UNDER THE INFLUENCE OF THE UPPER LEVEL RIDGING IS GENERATING WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS S OF 20N W OF 79W...INCLUDING INLAND PORTIONS OF CENTRAL AMERICA. FARTHER SOUTH OVER THE SW CARIBBEAN...CLOSE PROXIMITY OF THE MONSOON TROUGH AXIS ALONG 09N IS GENERATING SCATTERED SHOWERS AND TSTMS S OF 10N BETWEEN 72W-77W AND S OF 09N BETWEEN 77W-80W ACROSS PORTIONS OF NORTHERN COLOMBIA AND EASTERN PANAMA. CHANTAL IS EXPECTED TO TRACK W-NW CLEARING THE BASIN BY LATE THURSDAY WITH E-SE TRADES RE-ESTABLISHING FOR THE UPCOMING WEEKEND. HISPANIOLA... CURRENTLY ISOLATED SHOWERS AND TSTMS ARE OCCURRING ACROSS THE ISLAND AS MOISTURE AND CLOUDINESS IS EXPECTED TO INCREASE OVER THE NEXT 24 TO 36 HOURS WITH TROPICAL STORM CHANTAL TRACKING TOWARDS THE SOUTH-CENTRAL COAST OF HISPANOLA. CHANTAL IS EXPECTED TO PRODUCE PLENTY OF RAINFALL...LOCALLY HEAVY AT TIMES...THROUGH EARLY THURSDAY ON TOP OF OTHER IMPACTS SUCH AS WIND AND STORM SURGE. ONCE CHANTAL MAKES ITS WAY INTO THE EASTERN FLORIDA STRAITS BY LATE THURSDAY INTO FRIDAY...E-SE TRADES ARE EXPECTED TO RESUME WITH THE MORE TYPICAL AFTERNOON SHOWERS AND TSTMS OCCURRING ACROSS THE ISLAND DURING THE WEEKEND. ATLANTIC OCEAN... AN UPPER LEVEL LOW IS CENTERED OVER THE FLORIDA STRAITS NEAR 24N80W THAT IS PROVIDING THE SW NORTH ATLC S OF 28N W OF 75W WITH WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS THIS EVENING. THIS AREA INCLUDES EASTERN CUBA AND PORTIONS OF THE CENTRAL AND NW BAHAMAS. OTHERWISE...THE REMAINDER OF THE SW NORTH ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1025 MB HIGH CENTERED IN THE VICINITY OF BERMUDA NEAR 33N64W. THE HIGH IS EXPECTED TO REMAIN FAIRLY STATIONARY OVER THE NEXT 24 TO 36 HOURS AS TROPICAL STORM CHANTAL TRACKS ON ITS SOUTHERN AND SOUTHWESTERN PERIPHERY FOR THE REMAINDER OF THE WEEK. FARTHER EAST...AN UPPER LEVEL LOW IS CENTERED NEAR 33N54W THAT SUPPORTS A SURFACE TROUGH THAT IS ANALYZED INTO THE DISCUSSION AREA ALONG 32N49W TO 30N53W. ISOLATED SHOWERS ARE POSSIBLE WITHIN 90 NM EAST OF THE BOUNDARY. ANOTHER UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY IN THE VICINITY OF 38N34W THAT SUPPORTS A SURFACE TROUGH FROM 32N38W TO 26N45W. ISOLATED SHOWERS ARE OCCURRING WITHIN 120 NM EAST OF THE SURFACE TROUGH AXIS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN