000 AXNT20 KNHC 270542 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT TUE OCT 27 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 0515 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 04N28W TO 11N26W MOVING W AT 10-15 KT. THE WAVE COINCIDES WITH A RELATIVELY LOW-AMPLITUDE 700 MB TROUGH BETWEEN 23W-31W. REMAINING EMBEDDED WITHIN THE MONSOON TROUGH AND ITCZ REGION...SCATTERED MODERATE CONVECTION IS FROM 03N-11N BETWEEN 24W-31W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 11N15W TO 07N23W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N32W TO 06N40W TO 09N47W. SCATTERED MODERATE CONVECTION IS FROM 05N-11N BETWEEN 19W-24W...FROM 04N-11N BETWEEN 27W- 43W...AND FROM 11N-13N BETWEEN 44W-49W. THE WESTERN AREA OF CONVECTION IS ASSOCIATED WITH A SURFACE TROUGH ANALYZED FROM 09N50W-15N47W AND LIES BENEATH AN AREA OF MAXIMUM UPPER LEVEL DIFFLUENCE. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY PROGRESSING OVER THE SE CONUS THIS EVENING IN SUPPORT OF A 1002 MB LOW CENTERED ACROSS SE LOUISIANA NEAR 30N91W. THIS PARTIALLY OCCLUDED LOW EXTENDS A COLD FRONT ACROSS THE FAR WESTERN FLORIDA PANHANDLE INTO THE NE GULF NEAR 30N87W SOUTHWARD TO THE YUCATAN PENINSULA NEAR 21N88W. GIVEN THE FAVORABLE MIDDLE TO UPPER LEVEL DIFFLUENCE IN THE VICINITY OF AND EAST OF THE SHORTWAVE...SCATTERED TO NUMEROUS SHOWERS AND WIDELY SCATTERED TSTMS ARE OCCURRING N OF 24N EAST OF THE COLD FRONT ACROSS THE NE GULF WATERS AND PORTIONS OF THE FLORIDA PENINSULA...AND WITHIN 60 NM EITHER SIDE OF THE COLD FRONT S OF 24N...INCLUDING PORTIONS OF THE YUCATAN PENINSULA. OTHERWISE...OVERCAST SKIES IN LOW STRATUS AND FOG WITH LOCALLY LIMITED VISIBILITIES ARE NOTED IN SHIP...BUOY...AND OIL PLATFORM OBSERVATIONS N OF 25N W OF 88W. FRESH TO STRONG SOUTHERLY WINDS ARE OBSERVED EAST OF THE FRONT...WHILE GENTLE TO FRESH W-NW WINDS ARE OBSERVED WEST OF THE FRONT. BY LATE WEDNESDAY INTO EARLY THURSDAY THE FRONT IS EXPECTED TO MOVE EAST OF THE BASIN WITH HIGH PRESSURE ANCHORING ITSELF ACROSS THE WESTERN GULF THEN MOVING NE THROUGH FRIDAY. CARIBBEAN SEA... THE MAIN FEATURE INFLUENCING WEATHER ACROSS THE EASTERN CARIBBEAN IS A MIDDLE TO UPPER LEVEL TROUGH WITH AXIS EXTENDING FROM NEAR 24N68W TO A BASE OVER NORTHERN COLOMBIA NEAR 12N74W. SCATTERED SHOWERS AND TSTMS ARE OCCURRING PRIMARILY N OF 14N BETWEEN 63W-71W...INCLUDING EASTERN HISPANIOLA...PUERTO RICO... AND THE LEEWARD ISLANDS. OTHERWISE...N-NE FLOW ALOFT WEST OF THE UPPER LEVEL TROUGH AXIS IS PROVIDING FOR MOSTLY CLEAR SKIES AND FAIR CONDITIONS THIS EVENING. LATEST SCATTEROMETER DATA DEPICTS MOSTLY MODERATE TO FRESH BREEZE CONDITIONS...OUTSIDE OF THE ACTIVE ONGOING CONVECTION...THAT IS FORECAST TO PERSIST THROUGH FRIDAY. ...HISPANIOLA... AN UPPER-LEVEL TROUGH AXIS CONTINUES TO EXTEND OVER EASTERN PORTIONS OF THE ISLAND WITH SCATTERED SHOWERS AND ISOLATED TSTMS PREVAILING E OF 71W...INCLUDING THE MONA PASSAGE AND ADJACENT COASTAL WATERS. LITTLE CHANGE IS EXPECTED ACROSS THE ISLAND DURING THE NEXT 24 HOURS. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY IN THE VICINITY OF 32N81W MOVING NE THIS EVENING. THE SHORTWAVE SUPPORTS A COLD FRONT ANALYZED FROM 33N70W SW TO THE GEORGIA AND FLORIDA BORDER NEAR 31N81W. MIDDLE TO UPPER LEVEL DIFFLUENCE IS MAXIMIZED OFFSHORE OF GEORGIA AND THE CAROLINAS GENERATING SCATTERED SHOWERS AND TSTMS N OF 27N W OF 74W. FARTHER EAST...AN ELONGATED UPPER LEVEL LOW IS CENTERED NEAR 23N68W THAT SUPPORTS A SURFACE TROUGH ANALYZED FROM 20N67W TO 29N64W. WHILE MOST OF THE STRONGER UPPER LEVEL DIFFLUENCE IS NOTED OVER THE NE CARIBBEAN SEA...MOISTURE CONTINUE TO ADVECT NORTHWARD EAST OF THE UPPER LEVEL TROUGH AXIS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS FROM 18N-28N BETWEEN 58W- 69W. THIS AREA FALLS WITHIN A WEAKNESS IN SURFACE RIDGING ACROSS THE SW NORTH ATLC AND CENTRAL ATLC BETWEEN 53W-67W. OTHERWISE... THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1026 MB HIGH CENTERED NEAR 32N41W. ONE EXCEPTION TO THE RIDGE IS A WEAKENING COLD FRONT ON THE SOUTHEASTERN PERIPHERY OF THE RIDGE ANALYZED FROM 32N14W SW TO 28N26W TO 31N36W. POSSIBLE ISOLATED SHOWERS ARE WITHIN 90 NM EITHER SIDE OF THE BOUNDARY. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN