000 AXPZ20 KNHC 191513 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC MON JAN 19 2015 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. ...SPECIAL FEATURE... GULF OF TEHUANTEPEC GALE WARNING...THE PRESSURE GRADIENT BETWEEN STRONG HIGH PRESSURE OVER EASTERN MEXICO AND LOWER PRESSURE ASSOCIATED WITH A SURFACE TROUGH OVER THE FAR EASTERN NORTH PACIFIC IS MAINTAINING STRONG GALE FORCE WINDS OVER THE GULF OF TEHUANTEPEC. HIGH PRESSURE WILL SHIFT NE AND WINDS OVER THE SW GULF OF MEXICO WILL VEER BY WED. THIS WILL DECREASE WINDS FUNNELING INTO THE GULF OF TEHUANTEPEC AND WINDS WILL DIMINISH BELOW GALE FORCE BY WED AFTERNOON. SEAS ARE EXPECTED TO BUILD UP TO 16-17 FT WITH THE STRONGEST WINDS. NE TO E SWELL ASSOCIATED WITH THIS EVENT COMBINED WITH A GALE WIND EVENT OVER THE GULF OF PAPAGAYO IS FORECAST TO PRODUCE A VERY LARGE AREA OF SEAS 8 FT OR GREATER THAT WILL EXTEND SW TO BEYOND 100W. SEE LATEST HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFEP2/FZPN03 KNHC FOR ADDITIONAL DETAILS. GULF OF PAPAGAYO GALE WARNING...NE WINDS OF 30-35 KT EXTEND INTO THE GULF OF PAPAGAYO AND DOWNWIND OF THE GULF WITH SEAS IN THE 8- 12 FT RANGE TO NEAR 92W/93W. WINDS ARE FORECAST TO DIMINISH JUST BELOW GALE FORCE EARLY WED. NE SWELL GENERATED FROM THIS EVENT WILL MIX WITH CROSS EQUATORIAL SW SWELL AND NORTHERLY SWELL FROM THE TEHUANTEPEC EVENT ACROSS THE WATERS E OF 100W. SEE LATEST HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFEP2/FZPN03 KNHC FOR ADDITIONAL DETAILS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A SURFACE TROUGH EXTENDS FROM 04N77W TO 04N95W. THE ITCZ EXTENDS FROM 04N95W TO06.5N110W TO 02N122W TO 01N140W. SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 90 NM N OF THE SURFACE TROUGH BETWEEN 87W AND 93W. SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 90 NM N OF THE ITCZ BETWEEN 111W AND 116W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS NOTED WITHIN 90 NM OF THE ITCZ BETWEEN 130W AND 137W. ...DISCUSSION... HIGH PRESSURE OF 1024 MB CENTERED NEAR 27N127W EXTENDS A RIDGE SE TO NEAR 18N110W AND SW TO BEYOND 25N140W. THE PRESSURE GRADIENT BETWEEN THE AREA OF HIGH PRESSURE AND LOWER PRESSURE IN THE VICINITY OF THE ITCZ IS MAINTAINING FRESH TO STRONG TRADES FROM 05N TO 15N W OF 128W. THE AREA OF HIGH PRESSURE WILL WEAKEN OVER THE NEXT 24 HOURS AND TRADES N OF THE ITCZ OVER THE WESTERN WATERS WILL DIMINISH TO 20 KT OR LESS BY THURSDAY. A COLD FRONT WILL MOVE INTO THE NW WATERS WED NIGHT. SW WINDS AHEAD OF THE FRONT WILL INCREASE TO NEAR GALE FORCE OVER THE FAR NW WATERS WED. THE FRONT WILL PROPAGATE INTO THE AREA AND REACH FROM 30N135W TO 26N140W BY THU MORNING. THIS FRONT WILL USHER IN A FRESH SET OF NW SWELLS WITH COMBINED SEAS REACHING NEAR 20 FT BY THU MORNING OVER THE FAR NW WATERS. LARGE AND LONG PERIOD NW SWELL...22-23 SECONDS...CONTINUES TO PROPAGATE ACROSS THE FORECAST AREA. THE LEADING EDGE OF THIS SWELL EVENT HAS REACHED THE WATERS E OF 100W MIXING WITH CROSS EQUATORIAL SW SWELL AND NORTHERLY SWELL GENERATED IN THE GAP WIND REGIONS. AS A RESULT...SEAS 8 FT OR GREATER DOMINATES MOST OF THE FORECAST WATERS. THE EXCEPTIONS ARE THE GULF OF CALIFORNIA AND LEE OF THE GALAPAGOS ISLANDS. NORTHERLY WINDS IN THE 20-30 KT RANGE ARE FUNNELING FROM THE SW CARIBBEAN INTO THE GULF OF PANAMA EXTENDING DOWNSTREAM TO NEAR 03N WITH SEAS IN THE 8-10 FT RANGE. WINDS ARE EXPECTED TO DIMINISH TO 20-25 KT BY TONIGHT WITH SEAS SUBSIDING TO 8-9 FT AS THE PRES GRADIENT OVER THE WESTERN CARIBBEAN LOOSENS. $$ AL