000 AXPZ20 KNHC 091601 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC SUN OCT 09 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1545 UTC. ...SPECIAL FEATURES... HURRICANE JOVA CENTERED NEAR 16.2N 108.7W AT 09/1500 UTC MOVING E OR 090 DEG AT 5 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 978 MB. MAXIMUM SUSTAINED WIND SPEED IS 80 KT WITH GUSTS TO 100 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC FOR MORE DETAILS. NUMEROUS MODERATE TO STRONG CONVECTION IS WITHIN 150 NM OF THE CENTER IN THE SE SEMICIRCLE. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ELSEWHERE WITHIN 240 NM OF THE CENTER. LATEST NHC ADVISORY FORECASTS JOVA TO GRADUALLY INTENSIFY AS IT CONTINUES ON AN EASTWARD MOTION THROUGH THE NEXT 24 HRS...AND MOVING INLAND MEXICO NEAR 20N105W BY EARLY WED. INTERESTS IN AND NEAR THAT PART OF MEXICO SHOULD CAREFULLY MONITOR THE LATEST NHC ADVISORY INFORMATION FOR LIKELY POSSIBLE FUTURE HAZARDOUS STATEMENTS AS JOVA NEARS THE COAST. TROPICAL STORM IRWIN CENTERED NEAR 15.2N 119.8W AT 09/1500 UTC MOVING NE OR 055 DEG AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS. DEEP CONVECTION IS BEGINNING TO FIRE UP WITHIN 150 NM OF THE CENTER IN THE SW QUADRANT. LATEST NHC ADVISORY FORECASTS IRWIN TO REMAIN ON A NE TRACK THROUGH THE NEXT 24 HRS...THEN PERHAPS TURN MORE IN A SELY DIRECTION TO NEAR 16N115W BY 48 HRS WITH LITTLE IF ANY CHANGE IN INTENSITY...HOWEVER STRENGTHENING IS VERY POSSIBLE THEREAFTER. A 1006 MB LOW PRES IS LOCATED NEAR 11N96W...OR ABOUT 300 NM SW OF THE BORDER OF MEXICO AND GUATEMALA. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 150 NM OF THE LOW IN THE NW QUADRANT ...AND WITHIN 90 NM OF THE LOW IN THE SW QUADRANT. THE LOW LEVEL LEVEL CENTER REMAINS EXPOSED TO THE E OF THE DEEP CONVECTION AS UPPER LEVEL WINDS NLY WINDS REMAIN QUITE STRONG. HOWEVER... FORECAST GUIDANCE SUGGESTS THAT THE UPPER LEVEL WINDS ARE EXPECTED TO BECOME MORE FAVORABLE TO ALLOW FOR DEVELOPMENT OF THE LOW TO TRANSPIRE OVER THE NEXT 48 HRS A THE LOW TRACKS TO THE E-NE. WINDS OF 20-30 KT WITH SEAS OF 8-11 FT ARE FORECAST WITHIN 60 NM OF THE LOW IN 48 HRS. A HIGH CHANCE FOR POTENTIAL TROPICAL CYCLONE FORMATION WILL EXIST WITH THE LOW DURING THE NEXT 48 HRS. 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 AXIS IS ANALYZED FROM 13N87W TO 13N90W TO LOW PRES NEAR 11N96W WHERE IT ENDS DUE TO A BREAK IN THE TROUGH AS A RESULT OF THE CIRCULATION AROUND HURRICANE IRWIN AND TROPICAL STORM JOVA. LOW LEVEL WINDS THEN SUGGEST THAT THE MONSOON TROUGH CONTINUES FROM 12N127W...THEN ITCZ AXIS TO 8N140W. SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 120 NM EITHER SIDE OF AXIS E OF 91W WITH NUMEROUS MODERATE TO STRONG CONVECTION IS ELSEWHERE N OF 6N BETWEEN 81W AND 89W. ...DISCUSSION... THE 1025 MB SUBTROPICAL HIGH PRES IS CENTERED N OF THE AREA NEAR 32N139W WITH A RIDGE AXIS EXTENDING SE TO NEAR 23N122W. THE PRES GRADIENT BETWEEN THIS RIDGE AND LOWER PRES ASSOCIATED WITH TROPICAL STORM IRWIN AND HURRICANE JOVA CONTINUES TO PRODUCE FRESH NE TRADES FROM 18N-25N W OF 120W...AND FROM 25N-28N W OF 135W. THESE TRADES WILL SHRINK TO W OF 135W OVER THE NEXT 24 HOURS AS THE SUBTROPICAL HIGH MOVES SW AND IRWIN AND JOVA MOVE E...AND FROM 21N-27N BETWEEN 126W-135W. THE PRES GRADIENT BETWEEN THE RIDGE AND TROUGHING OVER INLAND MEXICO IS MAINTAINING FRESH NW TO N WINDS OVER THE GULF OF CALIFORNIA FROM 27N TO 30N WHICH WILL DIMINISH THIS AFTERNOON AS THE HIGH SHIFTS WSW. ON MON...THE NE MOTION OF IRWIN WILL ERODE THE SOUTHERN EDGE OF THE RIDGE AND SHIFT THE STRONGEST PRES GRADIENT TO OVER N CENTRAL WATERS WHERE FRESH N WINDS WILL DEVELOP. BY LATE MON...THE SUBTROPICAL HIGH WILL RETROGRADE INTO THE NW PORTION OF THE AREA SHIFTING THE AREA OF TRADES BACK TO THE E. 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. ACROSS THE EASTERN WATERS...WINDS ARE EXPECTED TO INCREASE TO STRONG AND MERGE WITH THE LOW PRES DISCUSSED IN THE SPECIAL FEATURES SECTION AS PRESSURES FALL ALONG THE MONSOON TROUGH AND AROUND THIS LOW. THE STRENGTHENING SW FLOW OVER EASTERN WATERS WILL MAINTAIN LOW LEVEL CONFLUENCE AND CONTINUE TO PRODUCE ACTIVE CONVECTION NEAR THE MONSOON TROUGH. 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 10 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 TODAY BEFORE THE SW SWELL BECOMES THE DOMINANT SWELL COMPONENT ...AND BUILDS TO 12 FT IN 48 HRS. A NEW PULSE OF NW SWELL WILL PROPAGATE INTO THE FORECAST AREA TONIGHT INTO MON OVER THE PORTION OF THE AREA N OF 26N BETWEEN 123W-131W WHERE N-NE 20 KT ARE EXPECTED. THIS SWELL WILL KICK UP SEAS TO 8 FT BY EARLY ON MON...AND TO 9 FT ON TUE N OF 29N BETWEEN 120W-125W WHERE N WINDS OF 20 KT ARE EXPECTED. $$ AGUIRRE