000 AXPZ20 KNHC 190957 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC MON NOV 19 2012 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0900 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH EXTENDS FROM 10N74W TO 08N78W TO 10N84W TO 05N93W WHERE IT TRANSITIONS TO ITCZ...CONTINUING TO 08N113W TO 07N131W TO BEYOND 08N140W. SCATTERED MODERATE TO STRONG CONVECTION NOTED WITHIN 90 NM N AND 120 NM S OF ITCZ AXIS W OF 120W. ...DISCUSSION... ALOFT...AN UPPER LEVEL TROUGH EXTENDS FROM SOUTHERN NEVADA SW AND ENTERS THE FORECAST REGION NEAR 30N120W THEN CONTINUES SW TO NEAR 19N130W. TROUGH HAS SWEPT SE PAST 24 HOURS WITH DEVELOPING ELONGATED VORT CENTER APPARENT IN WATER VAPOR IMAGERY ALONG 25N123.5W ALIGNING SOUTHERN END OF TROUGH MORE NNE TO SSW. STRONG NW JET TO 120 KT PER RECENT CIMSS ANALYSIS DIVING SE THROUGH BASE OF TROUGH AND PRODUCING STRONG UPPER CONVERGENCE NEAR 10N119W. DOWNSTREAM UPPER RIDGE HAS SHIFTED SLIGHTLY EWD DUE TO DIGGING UPPER TROUGH...AND REMAINS CENTERED ON ANTICYCLONE NEAR 15N100W...AND COVERS THE AREA N OF 10N BETWEEN 90W AND 115W. A SUBTROPICAL JET EXITS THE BASE OF UPPER TROUGH TO W AND FLOWS NE OVER RIDGE...CONTINUING NE ACROSS BAJA CALIFORNIA AND NW MEXICO INTO THE SW CONUS...TRANSPORTING ABUNDANT MID/UPPER LEVEL MOISTURE. SATELLITE IMAGERY CONTINUES TO SHOWS A WIDE BAND OF TRANSVERSE HIGH CLOUDS IN ASSOCIATION WITH THIS JET. TO THE E OF THE RIDGE...PERSISTENT UPPER TROUGH EXTENDS FROM A CUT-OFF LOW JUST OFF THE SE U.S. COAST...S-SW ACROSS THE NW BAHAMAS AND THE NW CARIBBEAN TO CENTRAL AMERICA NEAR 14N91W. A LINGERING TUTT AXIS STRETCHES FROM 10N89W TO A CYCLONIC CIRCULATION NEAR 04N111W. SW FLOW IS NOTED E OF 90W FROM THE EQUATOR ACROSS COSTA RICA AND PANAMA INTO THE CARIBBEAN SEA. MODERATE TO STRONG SUBSIDENCE OCCURRING N OF THE TUT AXIS CONTINUES TO DOMINATE THE AREA E OF 105W...AND IS LIMITING CONVECTION ALONG THE MONSOON TROUGH AND THE ITCZ AXIS. AT THE SURFACE...A WEAK AND NARROW RIDGE CONTINUES TO BUILD ACROSS THE NORTHERN WATERS FROM THE W-NW...BUT IS CREATING SUFFICIENT PRES GRADIENT TO THE S TO PRODUCE FRESH NE TO E TRADE WINDS FROM 09N TO 20N W OF 120W. EXPECT THE RIDGE TO STRENGTHEN SLIGHTLY DURING THE NEXT 24 HOURS...AND A NEW HIGH CENTER TO REFORM NEAR 29N124W BY THIS AFTERNOON...WHICH WILL MAINTAIN A FAIRLY BROAD ZONE OF NE TO E WINDS 20-25 KT FROM 09N TO 20N W OF 120W WITH SEAS OF 8 TO 11 FT ACROSS THIS AREA. LONG PERIOD NW SWELL CONTINUES TO INVADE THE REGIONAL WATERS MAINLY W OF 110W AND NOW ARE RAISING SEAS TO 13 FT N OF 28N. THESE SWELLS WILL COMBINE WITH NE WIND WAVES DEVELOPING WITHIN THE TRADE WIND ZONE TO MAINTAIN COMBINED SEAS OF 8 TO 10 FT WITHIN THE TRADE WIND BELT. THE NEXT PULSE OF INCREASING NW SWELL IS EXPECTED TO REACH THE N WATERS LATE WED. GAP WINDS... PERSISTENT NORTHERLY WINDS OF 25-30 KT ARE BLOWING THROUGH THE GULF OF TEHUANTEPEC...AS MODERATE NLY WINDS CONTINUE ACROSS THE SW GULF OF MEXICO. WINDS EXITING THE CHIVELAS PASS CONTINUE TO BE ENHANCED BY NOCTURNAL DRAINAGE FLOW ACROSS THE GULF OF TEHUANTEPEC...AND HAVE BEEN REACHING MINIMAL GALE FORCE ROUGHLY BETWEEN 0600 AND 1200 UTC EACH OF THE PAST FEW DAYS. GLOBAL MODELS SUGGEST THAT THIS PATTERN WILL CONTINUE THROUGH WEDNESDAY BEFORE WINDS ACROSS THE SW GULF BEGIN TO TURN MORE E AND DIMINISH INFLUENCE ACROSS THE CHIVELAS PASS. A GALE WARNING THEREFORE REMAINS IN EFFECT FOR THE GULF TEHUANTEPEC THROUGH WEDNESDAY MORNING...WITH WINDS LIKELY AT OR JUST BELOW GALE FORCE OCCURRING DURING THE AFTERNOON HOURS. SEE LATEST NHC HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS HSFEP2/FZPN03 KNHC FOR DETAILS. PULSING OF NOCTURNAL WINDS ARE ALSO EXPECTED TO CONTINUE ACROSS THE GULF OF PAPAGAYO...WITH NOCTURNAL WINDS FORECAST TO REACH AROUND 20 KT FROM 0600 TO 1200 UTC...WITH SEAS OF 6-7 FT THROUGH AND DOWNWIND OF THE GULF. $$ STRIPLING