000 AXNT20 KNHC 100543 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SAT OCT 10 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 10N29W TO 20N26W MOVING W AT 10-15 KT. THE WAVE COINCIDES WITH A RELATIVELY SHARP 700 MB TROUGH AXIS WITH THE TROUGHING INFLUENCING THE WATERS BETWEEN 25W-35W. TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE EMBEDDED IN A MOISTURE MAXIMUM STRETCHING FROM THE NORTHWESTERN CAPE VERDE ISLANDS NEAR 18N26W SW TO NEAR 11N26W. SCATTERED MODERATE CONVECTION IS FROM MOSTLY WEST OF THE WAVE AXIS FROM 12N-17N BETWEEN 28W-33W. TROPICAL WAVE EXTENDS FROM 09N47W TO 16N47W MOVING W AT 10-15 KT. THE WAVE REMAINS DIFFICULT TO DISCERN ON SATELLITE IMAGERY AND GLOBAL MODEL DATA WHILE REMAINING EMBEDDED WITHIN THE ITCZ. ISOLATED MODERATE CONVECTION IS FROM 10N-12N BETWEEN 46W-48W. TROPICAL WAVE EXTENDS FROM 12N70W TO 20N69W MOVING W AT 10-15 KT. THE WAVE COINCIDES WITH 700 MB TROUGHING BETWEEN 65W-74W WITH A MAXIMUM IN 850 MB RELATIVE VORTICITY AT THE SOUTHERN EXTENT OF THE AXIS BETWEEN 68W-73W. MOVING BENEATH AN UPPER LEVEL LOW CENTERED OVER HISPANIOLA...ISOLATED MODERATE CONVECTION IS OCCURRING WITHIN 150 NM EITHER SIDE OF A LINE FROM 12N64W TO THE MONA PASSAGE NEAR 18N68W TO 19N75W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM THE AFRICAN COAST NEAR 10N14W TO 08N19W TO 12N29W TO 11N40W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 11N40W TO 07N59W. OUTSIDE OF CONVECTION ASSOCIATED WITH THE TROPICAL WAVES...SCATTERED MODERATE CONVECTION IS FROM 07N-12N BETWEEN 12W-17W...AND WITHIN 150 NM EITHER SIDE OF A LINE FROM 15N29W TO 10N43W. ISOLATED MODERATE CONVECTION IS FROM 05N-09N BETWEEN 18W-24W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL ANTICYCLONE IS CENTERED OVER THE SOUTH- CENTRAL GULF NEAR 23N90W AND IS PROVIDING A MOSTLY DRY AND STABLE AIRMASS FOR THE SOUTHERN HALF OF THE BASIN. TO THE NORTH...A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER THE LOWER MISSISSIPPI RIVER VALLEY THAT CONTINUES TO MOVE SOUTHEASTWARD AND SUPPORT STRONG WESTERLY FLOW ALOFT GENERALLY N OF 27N. IN ADDITION...THE TROUGHING SUPPORTS A COLD FRONT CURRENTLY ANALYZED FROM THE DELMARVA REGION SW TO EASTERN TEXAS. AS THE FRONT REMAINS NORTH OF THE GULF...GENTLE TO OCCASIONAL MODERATE NORTHEASTERLY WINDS ARE EXPECTED THROUGH THE OVERNIGHT HOURS INTO SATURDAY. HOWEVER BY EARLY SUNDAY...THE COLD FRONT IS EXPECTED ACROSS THE NE AND NORTH-CENTRAL GULF WATERS SHIFTING WINDS MORE NORTHERLY AS HIGH PRESSURE SETTLES IN ACROSS THE WESTERN GULF LATE SUNDAY INTO MONDAY. CARIBBEAN SEA... A BROAD UPPER LEVEL LOW IS CENTERED SOUTH OF HISPANIOLA NEAR 17N72W INFLUENCING MUCH OF THE BASIN THIS EVENING. WEST OF 72W...WATER VAPOR IMAGERY INDICATES MOSTLY DRY AND STABLE NORTHERLY FLOW ALOFT WITH ONLY A FEW DIMINISHING ISOLATED SHOWERS AND TSTMS LINGERING OFFSHORE OF THE GREATER ANTILLES AS A RESULT OF EARLIER AFTERNOON AND EVENING CONVECTION. EAST OF 72W...RELATIVELY MOIST SOUTHWESTERLY FLOW ALOFT ALONG WITH A TROPICAL WAVE ANALYZED ALONG 70W IS PROVIDING A FAIRLY UNSTABLE ENVIRONMENT ACROSS THE EASTERN CARIBBEAN SUPPORTING ISOLATED SHOWERS AND POSSIBLE ISOLATED TSTMS W OF A LINE FROM WESTERN HISPANIOLA NEAR 19N75W TO NE VENEZUELA NEAR 11N65W. OTHERWISE... MODERATE TO FRESH TRADES PERSIST ACROSS THE BASIN WITH THE STRONGEST WINDS NOTED S OF 15N BETWEEN 67W-77W. ...HISPANIOLA... CURRENTLY AN UPPER LEVEL LOW CENTERED S OF THE ISLAND COMBINED WITH THE PRESENCE OF A TROPICAL WAVE ALONG 70W IS PROVIDING FOR INCREASED MOISTURE AND CLOUDINESS ACROSS THE REGION. ISOLATED SHOWERS AND TSTMS ARE EXPECTED TO CONTINUE ACROSS THE ISLAND THROUGH THE OVERNIGHT INTO SATURDAY AS A RESULT. AS THE TROPICAL WAVE MOVES WEST OF THE REGION AND THE UPPER LEVEL LOW WEAKENS BY MONDAY...CONDITIONS ARE EXPECTED TO IMPROVE INTO EARLY NEXT WEEK. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER THE SE CONUS THAT IS EXPECTED TO CONTINUE DRIFTING SE THROUGH THE REMAINDER OF THE WEEKEND. EMBEDDED WITHIN THIS TROUGHING IS A WEAKENING SHORTWAVE OFF THE COAST OF FLORIDA THAT SUPPORTS A 1015 MB LOW CENTERED NEAR 28N80W. A STATIONARY FRONT EXTENDS EASTWARD TO 28N70W AND INTO A 1012 MB LOW CENTERED NE OF BERMUDA NEAR 34N63W. SCATTERED SHOWERS AND TSTMS ARE OCCURRING WITHIN CLOSE PROXIMITY TO THE LOW FROM 27N-29N BETWEEN 77W-80W. ISOLATED SHOWERS ARE ALSO OCCURRING EAST OF THE NW BAHAMAS IN THE VICINITY OF 26N76W. THE WEAK LOW IS EXPECTED TO DRIFT NORTHWARD AND BECOME ABSORBED INTO A FRONTAL SYSTEM FORECAST TO ENTER THE SW NORTH ATLC LATE SATURDAY INTO SUNDAY. FARTHER EAST...ANOTHER SHORTWAVE TROUGH IS NOTED SOUTH OF THE PREVIOUSLY MENTIONED 1012 MB LOW NORTH OF THE AREA NEAR 34N63W THAT SUPPORTS A SURFACE TROUGH ANALYZED FROM 23N66W TO 30N59W. SCATTERED SHOWERS AND TSTMS ARE OCCURRING FROM 24N-29N BETWEEN 59W-65W. AND AREAS N OF 28N BETWEEN 46W-59W. FINALLY...THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1021 MB HIGH CENTERED NEAR 28N49W. ONE EXCEPTION TO THE RIDGING IS A DISSIPATING COLD FRONT EXTENDING FROM 32N15W SW TO 22N43W. ISOLATED SHOWERS ARE POSSIBLE WITHIN 90 NM EITHER SIDE OF THE FRONT. 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