000 AXPZ20 KNHC 120341 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC THU DEC 12 2013 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 0300 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC...N TO NE 30 TO 40 KT GALE FORCE WINDS CONTINUE TO SPREAD THROUGH THE GULF OF TEHUANTEPEC. WINDS ARE FORECAST TO INCREASE UP TO 45 KT DURING THE LATE NIGHT/EARLY MORNING HOURS TONIGHT WITH THE AIDE OF NOCTURNAL DRAINAGE FLOW THEN WILL DIMINISH SLIGHTLY BACK TO 30 TO 35 KT DURING THE DAY THU. EXPECT ANOTHER INCREASE BACK TO 40 KT OVERNIGHT THU NIGHT... DIMINISHING BELOW GALE FORCE BY 48 HOURS. THE LONG DURATION OF THESE WINDS WILL SEND A PLUME OF NE SWELL TO THE SW- W WELL AWAY FROM THE GULF OF TEHUANTEPEC...REACHING TO 115W BY 48 HOURS. MEANWHILE SIGNIFICANT WAVE HEIGHTS WILL PEAK AT 10 TO 17 FT DURING THE TIME OF THE STRONGEST WINDS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 08N78W TO 04N87W. THE ITCZ EXTENDS FROM 09N115W TO BEYOND 08N140W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 120 NM N OF THE ITCZ BETWEEN 110W AND 116W...WITHIN 90 NM S OF THE ITCZ BETWEEN 115W AND 118W...AND FROM 10N TO 12N BETWEEN 120W AND 124W. SCATTERED MODERATE CONVECTION FROM 09N TO 15N W OF 130W. ...DISCUSSION... A COLD FRONT IS JUST NW OF THE AREA. MODEL GUIDANCE DOES MANAGE TO MOVE IT JUST INTO THE NW CORNER EARLY THU BEFORE STALLING OUT LATER THU...THEN SHIFTING BACK W OF 140W AS A REMNANT TROUGH SHORTLY THEREAFTER. SEAS TO 8 FT IN NW SWELL WILL TOUCH 30N140W BUT WILL LIKELY REMAIN JUST OUTSIDE THE DISCUSSION WATERS. WEAKENING 1024 MB HIGH PRES IS AHEAD OF THE FRONT NEAR 34N130W WITH A BROAD RIDGE EXTENDING TO THE SE ACROSS THE DISCUSSION AREA THROUGH 32N125W TO 14N106W. THE PRESSURE GRADIENT BETWEEN THE RIDGING AND LOWER PRESSURES ALONG THE ITCZ IS TIGHT ENOUGH TO SUPPORT FRESH TRADES OVER THE W CENTRAL WATERS. NE WIND WAVES COMBINED WITH LONGER PERIOD NW SWELL IS RESULTING IN 8-9 FT SEAS W OF A LINE FROM 21N140W TO 15N128W TO 09N140W. THESE SEAS WILL GRADUALLY SUBSIDE TO LESS THAN 8 FT BY FRI AFTERNOON AS THE NW SWELL DECAYS. TO THE SE OF THE HIGH/RIDGING...SEMI-PERMANENT TROUGHING OVER NW MEXICO WILL INDUCE FRESH WINDS IN THE SOUTHERN GULF OF CALIFORNIA SPILLING S TO 20N. CURRENTLY MODEL GUIDANCE KEEPS WINDS NO HIGHER THAN 20 KT AND SEAS JUST LESS THAN 8 FT... ALTHOUGH ISOLATED STRONG WINDS CANNOT BE RULED OUT. GULF OF PAPAGAYO...WINDS WILL INCREASE TO FRESH TO STRONG WITHIN 60 NM EITHER SIDE OF A LINE FROM 11N86W TO 09N89W BY THU NIGHT INTO EARLY FRI AS TRADE WINDS IN THE WESTERN CARIBBEAN SEA INCREASE...THEN WILL DIMINISH TO 20 KT OR LESS BY LATE FRI AFTERNOON. $$ LEWITSKY