000 AXPZ20 KNHC 061606 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC TUE DEC 06 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 1500 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH FROM LOW PRES NEAR 05N78W 1008 MB TO 08N86W TO 05N98W TO 06N104W. ITCZ FROM 06N104W TO LOW PRES NEAR 09N116W 1009 MB TO 07N140W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION FROM 07N TO 12N BETWEEN 111W AND 116W. SCATTERED MODERATE CONVECTION WITHIN 30 NM N OF LINE W OF 130W. ...DISCUSSION... GULF OF TEHUANTEPEC...HIGH PRES BUILDING OVER THE CENTRAL PLAINS OF THE UNITED STATES HAS INCREASED THE PRES GRADIENT BETWEEN THE NORTHERN COAST OF THE ISTHMUS OF TEHUANTEPEC AND ITS SOUTHERN TERMINUS. SEA LEVEL PRES AT MINATITLAN ON THE NORTHERN COAST HAS RISEN TO 1023 MB COMPARED WITH 1012 MB AT IXTEPEC ON THE SOUTHERN END. MEANWHILE A STALLED COLD FRONT OVER THE SW GULF OF MEXICO WILL RECEIVE A REINFORCING SHOT OF COLD AIR LATER TODAY...AND PUSH THROUGH THE GULF TONIGHT. THIS WILL ALLOW A SHARP INCREASE IN GAP FLOW THROUGH THIS EVENING...WITH WINDS LIKELY REACH STRONG GALE FORCE BY LATE WED. GLOBAL MODELS SHOW A LARGE PLUME REACHING S TO SW OF THE GULF OF TEHUANTEPEC AS FAR AS 105W...GENERATING SWELL IN EXCESS OF 15 FT THROUGH THU. GULF OF CALIFORNIA...A 0503 UTC ASCAT PASS REVEALED STRONG NLY WINDS 20-25 KT BLOWING THROUGH THE ENTIRE GULF...WITH STRONGEST WINDS S OF 26N-27N. THE WINDS ARE BEING DRIVEN BY A PRESSURE GRADIENT SETTING UP FROM HIGH PRESSURE OVER THE WESTERN U.S. AND A TROUGH OVER CENTRAL MEXICO. THE SURFACE PRES GRADIENT WILL TIGHTEN THROUGH THE NEXT 48 HOURS OVER THIS REGION INCREASING WINDS TO UP TO 30 KT LATER THIS MORNING...WHICH WILL ALLOW FOR SEAS TO BUILD TO 8-10 FT ACROSS THE GULF WATERS AND SPILLING OUT JUST TO THE S OF THE GULF OF CALIFORNIA. A ZONE OF NE-E WINDS WILL BE FORCED ACROSS AND THROUGH PASSES IN THE BAJA CALIFORNIA PENINSULA AND INTO THE OPEN PACIFIC WATERS TO THE W OF THE PENINSULA THIS MORNING THROUGH LATE TUE NIGHT...PRODUCING 20-25 KT WINDS. THERE REMAINS THE POSSIBILITY FOR SMALL AREAS OF GALE FORCE WINDS WITHIN THE GULF LATER THIS MORNING THROUGH EARLY WEDNESDAY MORNING. FURTHER SOUTH...A PERSISTENT 1009 MB LOW PRES SYSTEM CENTERED NEAR 09N116W CONTINUES TO PUSH W AT 10 KT...WITHIN AN ACCOMPANYING SURFACE TROUGH FROM 13N113W TO 07N117W. SW UPPER SHEAR IS KEEPING SCATTERED MODERATE TO ISOLATED STRONG CONVECTION WITHIN 300 NM TO THE E OF THE TROUGH. THE LOW WILL CONTINUE TO SHIFT W THROUGH THE NEXT 48 TO 72 HOURS ALONG 09N...WITH FRESH TO STRONG NE TO E WINDS WITHIN 240 NM TO THE N...BETWEEN THE LOW AND HIGH PRES N OF THE AREA. A MODERATE PRES GRADIENT IS OVER THE NW WATERS BETWEEN A STRONG 1035 MB HIGH PRES WELL N OF THE AREA AT 46N138W AND LOWER PRES ASSOCIATED WITH THE ITCZ. NE TRADEWINDS ARE GENERALLY BELOW THE 20 KT THRESHOLD...EXCEPT FOR SOME 20 KT WINDS BETWEEN 18N AND 22N IN THE FAR WESTERN PORTION OF OUR AREA. SEAS THERE ARE RUNNING BETWEEN 8 AND 9 FT IN MIXED NE AND NW SWELL THAT COVERS MOST OF THE AREA W OF 110W. THESE SWELL WILL GRADUALLY DIMINISH OVER TIME AND ARE RESTRICTED TO W OF 130W BY 48 HOURS. THE NEXT LARGE SWELL EVENT SHOULD COMMENCE FRIDAY WITH LONG PERIOD NW SWELL REACHING THE NORTHWEST CORNER OF THE AREA. GULF OF PAPAGAYO...WINDS WILL CONTINUE TO PULSE TO AROUND 20 KT IN AND DOWNWIND OF THE GULF OF PAPAGAYO THROUGH THE NEXT 48 HOURS...MAINLY DURING THE LATE NIGHT AND EARLY MORNING HOURS DURING PEAK DRAINAGE FLOW OFF OF CENTRAL AMERICA. GIVEN THAT THESE WINDS DROP BELOW 20 KT DURING THE LATE MORNING AND AFTERNOON HOURS...THIS HAS NOT BEEN INCLUDED INTO THE HIGH SEAS FORECAST. $$ STRIPLING/CHRISTENSEN