000 AXNT20 KNHC 280550 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT WED OCT 28 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 07N30W TO 14N27W MOVING W AT 5 KT. THE WAVE COINCIDES WITH A RELATIVELY LOW-AMPLITUDE 700 MB TROUGH BETWEEN 35W-40W. REMAINING EMBEDDED WITHIN THE MONSOON TROUGH... SCATTERED MODERATE CONVECTION IS WITHIN 120 NM EITHER SIDE OF A LINE FROM 07N30W TO 15N24W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 11N15W TO 08N20W TO 07N33W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 07N33W TO 09N40W TO 11N51W. SCATTERED MODERATE CONVECTION IS FROM 08N-13N BETWEEN 39W-48W. ...DISCUSSION... GULF OF MEXICO... MIDDLE TO UPPER LEVEL LONGWAVE TROUGHING IS NOTED ON WATER VAPOR IMAGERY OVER THE CENTRAL PLAINS AND MID-MISSISSIPPI RIVER VALLEY THIS EVENING THAT SUPPORTS A BROAD AREA OF LOW PRESSURE ACROSS THESE TWO REGIONS. AN OCCLUDED 1005 MB LOW IS CENTERED ACROSS NW MISSISSIPPI WITH THE ASSOCIATED COLD FRONT EXTENDING FROM THE FLORIDA PANHANDLE NEAR 30N84W TO THE NE TIP OF THE YUCATAN PENINSULA NEAR 21N87W. ISOLATED SHOWERS AND TSTMS ARE OCCURRING PRIMARILY EAST OF THE FRONT...INCLUDING THE YUCATAN CHANNEL AND PORTIONS OF THE FLORIDA PENINSULA. AS OF 28/0300 UTC...A SECONDARY TROUGH IS ANALYZED WEST OF THE MAIN COLD FRONT AS A SURFACE TROUGH FROM SOUTHERN MISSISSIPPI TO 26N92W. ISOLATED SHOWERS ARE POSSIBLE N OF 26N BETWEEN 85W-92W. OTHERWISE...THE REMAINDER OF THE BASIN WEST OF THE FRONT IS UNDER THE INFLUENCE OF A WEAK SURFACE RIDGE ANCHORED BY A 1013 MB HIGH CENTERED NEAR 22N94W. GENERALLY LIGHT TO MODERATE BREEZE CONDITIONS PREVAIL OUTSIDE OF THE FRONTAL ZONE WITH THE ANTICYCLONIC FLOW EXPECTED TO DRIFT E-NE THROUGH THURSDAY AS THE FRONT EXITS THE BASIN TO THE EAST. CARIBBEAN SEA... THE MAIN FEATURE INFLUENCING WEATHER ACROSS THE EASTERN CARIBBEAN IS AN UPPER LEVEL LOW CENTERED NEAR 14N71W WITH THE ASSOCIATED TROUGH AXIS EXTENDING FROM 20N67W TO A BASE OVER EASTERN PANAMA NEAR 08N78W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING PRIMARILY WEST OF A LINE FROM THE MONA PASSAGE NEAR 18N68W TO THE NORTHERN COLOMBIA COAST NEAR 11N73W. OTHERWISE...RELATIVELY DRY AND STABLE N-NE FLOW ALOFT WEST OF THE UPPER LEVEL TROUGH AXIS IS PROVIDING FOR MOSTLY CLEAR SKIES AND FAIR CONDITIONS THIS EVENING ACROSS A LARGE PORTION OF THE WESTERN CARIBBEAN AND CENTRAL AMERICA. LATEST SCATTEROMETER DATA DEPICTS MOSTLY MODERATE TO FRESH BREEZE CONDITIONS. THIS OVERALL WIND REGIME IS FORECAST TO PERSIST THROUGH SATURDAY. ...HISPANIOLA... AN UPPER LEVEL TROUGH AXIS EXTENDS OVER THE MONA PASSAGE TO AN UPPER LEVEL LOW CENTERED NEAR 14N71W. ISOLATED SHALLOW SHOWERS ARE NOTED ACROSS THE ISLAND HOWEVER THE OVERALL TREND EXPECTED THROUGH WEDNESDAY IS A FAIRLY STABLE ENVIRONMENT DUE TO NE WINDS ALOFT...AND LIGHT TRADE WIND FLOW. LITTLE CHANGE IS EXPECTED ACROSS THE ISLAND DURING THE NEXT 24 HOURS. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL LONGWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER THE CENTRAL CONUS THAT SUPPORTS A COLD FRONT ANALYZED IN THE EASTERN GULF OF MEXICO AND A WARM FRONT ANALYZED NORTH OF THE DISCUSSION AREA. WHILE AN AREA OF DRIER AIR SKIRTS E-NE ACROSS THE FLORIDA PENINSULA AND FAR NORTHWESTERN SW NORTH ATLC WATERS...UPPER LEVEL DIFFLUENCE EAST OF 80W IS GENERATING A FEW ISOLATED SHOWERS AND TSTMS FROM 28N-32N BETWEEN 74W-78W. FARTHER EAST...A MIDDLE TO UPPER LEVEL LOW IS CENTERED NEAR 27N66W THAT SUPPORTS A SURFACE TROUGH ANALYZED FROM NE OF PUERTO RICO NEAR 19N64W TO THE SOUTHERN EXTENT OF A COLD FRONT NEAR 32N57W. MIDDLE TO UPPER LEVEL DIFFLUENCE IS MAXIMIZED EAST OF THE UPPER LEVEL LOW AND ALONG WITH LOW-LEVEL MOISTURE CONVERGENCE IS GENERATING SCATTERED SHOWERS AND TSTMS FROM 23N- 32N BETWEEN 52W-61W...WITH ISOLATED SHOWERS AND TSTMS OCCURRING ELSEWHERE FROM 18N-32N BETWEEN 58W-65W. THE SURFACE TROUGHING IS EXPECTED TO LIFT NORTH OF 32N BY LATE THURSDAY AS CENTRAL ATLC RIDGING BUILDS WESTWARD ACROSS THE SW NORTH ATLC. OTHERWISE... THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A PAIR OF 1024 MB HIGHS...ONE CENTERED NEAR 29N40W AND THE OTHER CENTERED NEAR 32N29W. ONE EXCEPTION TO THE RIDGE IS A WEAKENING COLD FRONT ON THE SOUTHEASTERN PERIPHERY OF THE RIDGE ANALYZED FROM 31N10W W- SW TO 25N20W TO 25N33W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN