000 AXPZ20 KNHC 260931 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SAT NOV 26 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0915 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH 09N84W TO 06N90W TO 07N102W. ITCZ AXIS 07N102W TO LOW PRES 10N116W 1011 MB TO 11N128W THEN RESUMES AT 09N132W TO 06N140W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS NOTED FROM 08N TO 11N BETWEEN 116W AND 118W. SIMILAR CONVECTION IS WITHIN 40 NM EITHER SIDE OF ITCZ AXIS FROM 134W TO 137W. ...DISCUSSION... A LONG WAVE UPPER TROUGH IS PROGRESSING E OVER CENTRAL N AMERICA WITH ITS MEAN AXIS EXTENDING S INTO THE DISCUSSION AREA ALONG 32N107W TO 18N112W. STRONG SW FLOW AHEAD OF THE TROUGH AXIS IS TRANSPORTING A PLUME OF MID/UPPER LEVEL MOISTURE ACROSS NORTHERN MEXICO INTO TEXAS. A RIDGE DOMINATES CENTRAL AND SE MEXICO AND NORTHERN CENTRAL AMERICA WHERE MODERATE TO STRONG UPPER LEVEL SUBSIDENCE IS NOTED. AN UPPER ANTICYCLONE IS NEAR 10N136W WITH A RIDGE N TO BEYOND 32N128W. UPPER LEVEL MOISTURE...ORIGINATING W OF THE AREA...IS MOVING NE ALONG THE PERIPHERY OF THE RIDGE... AFFECTING THE DISCUSSION AREA MAINLY N OF 15N W OF 135W. ANOTHER LONG WAVE UPPER TROUGH WILL GRADUALLY APPROACH THE FAR NW CORNER OF THE AREA BY SUN. THE ASSOCIATED COLD FRONT WILL REACH 30N140W TONIGHT AND EXTEND FROM 30N137W TO 27N140W SUN MORNING. NLY WINDS OF 20-25 KT ARE EXPECTED IN THE WAVE OF THE FRONT AS WELL AS LONG PERIOD NW SWELL WITH BUILDING SEAS OF 12 TO 16 FT. THE FRONT IS FORECAST TO BECOME STATIONARY OVER THE NW WATERS IN ABOUT 48 HOURS. THE REMNANT TROUGH OF KENNETH EXTENDS FROM 15N130W TO 10N132W AND IS EXPECTED TO CONTINUE W REACHING FROM 17N134W TO 12N135W LATE SAT. TIGHT PRES GRADIENT BETWEEN A HIGH PRES N OF AREA AND THE TROUGH IS PRODUCING A LARGE AREA OF NE WINDS IN THE 20 TO 25 RANGE FROM 13N TO 25N BETWEEN 120W AND 135W AND FROM 10N TO 21N W OF 135W WITH SEAS OF 10 TO 14 FT IN MIXED NE AND NW SWELL. GULF OF CALIFORNIA...NORTHERLY WINDS AT 15 TO 20 KT WILL INCREASE TO 20 TO 25 KT THIS AFTERNOON AND CONTINUE THROUGH EARLY SUN BEFORE DIMINISHING SOME LATE SUN. NEXT GULF OF TEHUANTEPEC EVENT IS FORECAST TO BEGIN EARLY SUN MORNING AS HIGH PRES BUILDS SWD INTO THE FAR WRN GULF OF MEXICO AND ALONG THE EASTERN SLOPES OF THE SIERRA MADRE MOUNTAINS OF MEXICO IN THE WAKE OF A STRONG COLD FRONT THAT WILL RACE SE ACROSS THE GULF OF MEXICO THIS WEEKEND. WINDS ARE EXPECTED TO INCREASE QUICKLY TO GALE FORCE BY LATE SUNDAY MORNING. COMPUTER MODEL GUIDANCE IS IN GENERAL AGREEMENT THAT WINDS WILL THEN INCREASE TO STORM FORCE (50 KT) SUN EVENING OR NIGHT. SEAS COULD BUILD IN EXCESS OF 18-20 FT IN ASSOCIATION WITH THESE STORM FORCE WINDS SUNDAY NIGHT. A STORM WARNING IS ALREADY IN EFFECT FOR THIS AREA. OF NOTE...THE MONTHLY DISTRIBUTION OF TEHUANTEPEC EVENTS SHOWS THAT THE LARGEST NUMBER OF GALE FORCE EVENTS OCCURS IN DECEMBER WHILE THE STORM FORCE EVENTS OCCUR MOST OFTEN IN JANUARY. THE PEAK MONTHS OF OCCURRENCES OF GALE AND STORM FORCE WIND EVENTS IN THE GULF OF TEHUANTEPEC ARE NOVEMBER THROUGH FEBRUARY. $$ GR