000 AXPZ20 KNHC 100318 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC MON OCT 10 2011 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0230 UTC. ...SPECIAL FEATURES... HURRICANE JOVA CENTERED NEAR 16.5N 107.3W AT 10/0300 UTC MOVING E OR 080 DEG AT 6 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 975 MB. MAXIMUM SUSTAINED WIND SPEED IS 85 KT WITH GUSTS TO 105 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC FOR MORE DETAILS. NUMEROUS MODERATE TO STRONG CONVECTION IS WITHIN 60 NM OF THE CENTER...WITH SCATTERED MODERATE CONVECTION ELSEWHERE WITHIN 90-120 NM IN THE NE SEMICIRCLE AND FROM 14N TO 16N BETWEEN 108W AND 112W. LATEST NHC ADVISORY FORECASTS JOVA TO GRADUALLY INTENSIFY AS IT CONTINUES ON AN E-NE MOTION THROUGH THE NEXT 24 HRS...AND MOVING VERY NEAR TO THE COAST OF MEXICO AT 19.1N104.8W IN 48 HOURS AS A 105 KT GUSTS TO 130 KT MAJOR HURRICANE. LARGE AND DANGEROUS WAVES ASSOCIATED WITH JOVA WILL BEGIN TO REACH THE COASTLINE ON MON. INTERESTS IN AND NEAR W CENTRAL MEXICO SHOULD CAREFULLY MONITOR THE LATEST NHC ADVISORY INFORMATION FOR RELATED WATCHES AND WARNINGS AFFECTING MEXICO. TROPICAL STORM IRWIN CENTERED NEAR 15.2N 118.7W AT 10/0300 UTC MOVING E OR 085 DEG AT 5 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 120-150 NM IN THE SW SEMICIRCLE OF THE CENTER. LATEST NHC ADVISORY FORECASTS IRWIN TO REMAIN ON A E-NE TRACK THROUGH THE NEXT 120 HRS WITH LITTLE CHANGE IN INTENSITY THROUGH 120 HOURS. A 1006 MB LOW LOCATED NEAR 11N95.5W IS DRIFTING W. ASSOCIATED CONVECTION IS AS DESCRIBED IN THE SECTION BELOW. THE LOW LEVEL LEVEL CENTER REMAINS EXPOSED TO THE E OF THE DEEP CONVECTION AS UPPER LEVEL NW-N WINDS REMAIN QUITE STRONG. HOWEVER...FORECAST GUIDANCE SUGGESTS THAT THE UPPER LEVEL WINDS ARE EXPECTED TO BECOME MORE FAVORABLE WHICH WOULD ALLOW FOR SLOW DEVELOPMENT OF THE LOW DURING THE NEXT 48 HRS A THE LOW TURNS MORE TO THE E-NE. WINDS OF 20-30 KT WITH SEAS OF 8-12 FT ARE FORECAST WITHIN 60 NM OF THE LOW IN 24 HOURS....INCREASING TO 33 KT WITH SEAS TO 12 FT WITHIN 90 NM IN ABOUT 48 HOURS. THIS LOW HAS A HIGH CHANCE FOR TROPICAL CYCLONE FORMATION DURING THE NEXT 48 HOURS. INTERESTS ALONG THE PACIFIC COASTS OF GUATEMALA...EL SALVADOR...HONDURAS...AND NICARAGUA SHOULD MONITOR THE PROGRESS OF THIS SYSTEM. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH IS ALONG 11N86W TO 1006 MB LOW PRES NEAR 11N95.5W WHERE THERE IS A BREAK IN THE TROUGH DUE TO THE CIRCULATION AROUND HURRICANE IRWIN AND TROPICAL STORM JOVA. THE MONSOON TROUGH RESUMES FROM 13.5N121W TO 10N130W TO 09N138W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 09N138W TO BEYOND 09N140W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 60 NM EITHER SIDE OF A LINE FROM 09N85W TO 07N97W...WITHIN 120 NM IN THE W SEMICIRCLE OF THE LOW CENTER... AND WITHIN 120 NM EITHER SIDE OF A LINE FROM 07N97W TO 11N104W. ...DISCUSSION... 1026 MB SUBTROPICAL HIGH PRES IS CENTERED NW OF THE AREA NEAR 31N149W...OR APPROXIMATELY 750 NM N-NE OF HILO HAWAII...WITH A RIDGE AXIS EXTENDING SE TO NEAR 23N115W. THE PRES GRADIENT BETWEEN THIS RIDGE AND LOWER PRES ASSOCIATED WITH TROPICAL STORM IRWIN AND HURRICANE JOVA CONTINUES TO PRODUCE A SMALL AREA OF FRESH NE TRADES FROM 17N TO 21N W OF 135W AS INDICATED BY EARLIER SCATTEROMETER PASSES. THESE TRADES ARE FORECAST TO DIMINISH WITHIN THE NEXT 24 HOURS AS THE SUBTROPICAL HIGH CONTINUES TO MOVE W-SW WHILE IRWIN AND JOVA MOVE E. AS THE NE MOTION OF IRWIN ERODES THE SOUTHERN EDGE OF THE RIDGE THE STRONGEST PRES GRADIENT WILL SHIFT TO OVER N CENTRAL WATERS WHERE FRESH N WINDS WILL DEVELOP IN 48 HOURS N OF 25N BETWEEN 118W AND 125W. MEANWHILE A DEVELOPING PRES GRADIENT BETWEEN THE RIDGE AND TROUGHING OVER INLAND MEXICO WILL BRING FRESH NORTHERLY WINDS OVER THE GULF OF CALIFORNIA FROM 23N TO 28N IN 24 HOURS...THEN EXPANDING TO ALMOST THE ENTIRE GULF FROM 23N TO 30N AND INCREASING TO 20-25 KT IN 48 HOURS. FRESH SOUTHWESTERLY MONSOON FLOW DOMINATES THE AREA S OF THE THREE SPECIAL FEATURES NOTED ABOVE. THE PRES GRADIENT IS STRONGEST BETWEEN HIGH PRES OVER THE EASTERN SOUTH PACIFIC AND BROAD LOW PRES OVER MUCH OF CENTRAL AMERICA AND COLOMBIA EXTENDING W TO ENCOMPASS IRWIN AND JOVA. 20-25 KT SW-W WINDS HAVE EXPANDED EASTWARD REACHING FROM 04N TO 11N BETWEEN 80W AND 100W WITH AN EARLIER SHIP REPORT FROM WDE5381 REPORTING 12 FT SEAS SW OF COSTA RICA. THESE WINDS WILL PERSIST THROUGH THE NEXT 24-48 HOURS WHICH WILL MAINTAIN LOW LEVEL CONFLUENCE AND WILL CONTINUE TO PRODUCE ACTIVE CONVECTION NEAR THE MONSOON TROUGH AS THIS PORTION OF THE AREA ALSO REMAINS UNDER BROAD ANTICYCLONIC FLOW. NW SWELL IS CONTINUING TO PROPAGATE THROUGH THE NORTHERN FORECAST WATERS AND IS MERGING WITH CROSS-EQUATORIAL SW SWELL OVER CENTRAL WATERS INCLUDING THE AREAS NEAR JOVA AND IRWIN. COMBINED SEAS ARE AS HIGH AS 11 FT IN THIS AREA WHERE MERGING SWELL COMBINED WITH FRESHLY GENERATED WIND WAVES IS CREATING A VERY CONFUSED AND CHAOTIC SEA STATE THAT IS EXPECTED TO PERSIST INTO EARLY TONIGHT BEFORE THE SW SWELL BECOMES THE DOMINANT SWELL COMPONENT...AND BUILDS TO 12 FT IN 48 HOURS. A NEW PULSE OF NW SWELL WILL PROPAGATE INTO THE FORECAST AREA N OF 28N BETWEEN 120W AND 128W BY MON NIGHT THROUGH TUE NIGHT. YET ANOTHER SET OF NW SWELL WILL BREACH THE FAR NW CORNER W OF A LINE FROM 30N135W TO 27N140W WITH SEAS TO 9 FT IN 48 HOURS. $$ LEWITSKY