000 AXPZ20 KNHC 211558 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC THU JAN 21 2016 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 FEATURES... GULF OF TEHUANTEPEC STORM WARNING...NORTHERLY WINDS HAVE DIMINISHED THIS MORNING AND ARE VEERING TO THE SOUTH. EXPECT GENTLE SOUTHERLY FLOW LATE THIS AFTERNOON INTO THE EVENING HOURS ALONG WITH SUBSIDING SEAS. HIGH PRESSURE WILL SURGE SOUTHWARD ALONG EASTERN MEXICO BY EARLY FRIDAY BEHIND A STRONG COLD FRONT WHICH WILL MOVE THROUGH THE WESTERN GULF OF MEXICO. THE PRESSURE GRADIENT NEAR THE TEHUANTEPEC AREA WILL TIGHTEN BETWEEN THIS HIGH PRESSURE AND LOWER PRESSURES TO THE SOUTH ASSOCIATED WITH THE ITCZ. AS A RESULT...EXPECT WINDS TO VERY RAPIDLY INCREASE TO GALE AND STRONG GALE BY SUNRISE FRIDAY WHILE SHIFTING TO THE NORTH INCREASING TO STORM FORCE BY LATE FRIDAY MORNING/EARLY AFTERNOON. STORM FORCE WINDS ARE EXPECTED TO PERSIST THROUGH THE OVERNIGHT HOURS FRIDAY...GRADUALLY DIMINISHING AFTER SUNRISE SATURDAY. SEAS WILL BUILD TO UP TO 20-22 FT FRIDAY NIGHT INTO EARLY SATURDAY. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A TROUGH AXIS EXTENDS FROM NW COLOMBIA NEAR 05N77W TO 02N80W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 02N85W TO 05N100W TO 06N110W TO 05N124W TO 03N140W. NO SIGNIFICANT CONVECTION IS NOTED. ...DISCUSSION... GULF OF CALIFORNIA...HIGH PRESSURE BUILDING OVER THE SW UNITED STATES TODAY THROUGH FRIDAY WILL SUPPORT THE DEVELOPMENT OF FRESH TO STRONG NW WINDS IN THE GULF OF CALIFORNIA. SEAS WILL BUILD TO 8 FT AS A RESULT OF THESE WINDS. WINDS WILL DIMINISH FRIDAY AFTERNOON AS THE PRESSURE GRADIENT RELAXES. GULF OF PAPAGAYO...FRESH TO STRONG NORTHEAST FLOW IN THE GULF OF PAPAGAYO WILL DIMINISH LATE THIS AFTERNOON INTO THE EARLY EVENING HOURS...THEN WILL RESUME LATE THIS EVENING THROUGH EARLY FRIDAY WITH THE AIDE OF NOCTURNAL DRAINAGE FLOW. WINDS WILL THEN DIMINISH AGAIN LATE FRIDAY MORNING THROUGH THE AFTERNOON HOURS WITH ANOTHER ROUND OF FRESH TO STRONG WINDS EXPECTED LATE FRIDAY NIGHT INTO EARLY SATURDAY. SEAS WILL BUILD TO 8 FT DURING THE STRONGEST WINDS. GULF OF PANAMA...FRESH TO STRONG N-NE WINDS OCCURRING IN THE WESTERN GULF OF PANAMA WILL DIMINISH LATE THIS MORNING. SEAS UP TO 8 FT DUE TO THESE WINDS WILL ALSO SUBSIDE BY LATE MORNING. A COLD FRONT IS LOCATED IN THE NW WATERS EXTENDING FROM 30N134W TO 26N140W. OVERNIGHT SCATTEROMETER DATA INDICATED FRESH TO STRONG SOUTHERLY FLOW N OF 26N WITHIN 240 NM AHEAD OF THE FRONT. LARGE NW SWELLS UP TO 18 FT ARE ARRIVING BEHIND THE FRONT. THE FRONT WILL GRADUALLY WEAKEN DURING THE NEXT 12-24 HOURS WITH WINDS DIMINISHING TO 20 KT OR LESS BY LATE TONIGHT INTO EARLY FRIDAY. MEANWHILE THE NW SWELL WITH SEAS OF 8 FT OR GREATER WILL PROPAGATE TO THE E-SE ACROSS THE MAJORITY OF THE WATERS W OF 110W BY LATE FRIDAY NIGHT INTO EARLY SATURDAY. THE NEXT COLD FRONT IS EXPECTED TO APPROACH 30N140W LATE SUNDAY NIGHT INTO EARLY MONDAY. HIGH PRESSURE AT 1023 MB IS LOCATED TO THE EAST OF THE COLD FRONT NEAR 32N122W WITH A RIDGE AXIS EXTENDING SOUTHEAST TO NEAR THE REVILLAGIGEDO ISLANDS...AS WELL AS TO THE SW TO NEAR 21N135W. THE PRESSURE GRADIENT BETWEEN THE RIDGING AND LOWER PRESSURE ASSOCIATED WITH THE ITCZ IS MAINTAINING MODERATE TO FRESH TRADES EXCEPT LOCALLY STRONG FROM 06N TO 09N BETWEEN 120W AND 128W. THE AREA OF HIGH PRESSURE WILL WEAKEN OVER THE NEXT 12- 24 HOURS WITH TRADES DIMINISHING SLIGHTLY. NEW HIGH PRESSURE WILL BUILD IN THE WAKE OF THE COLD FRONT DURING THE UPCOMING WEEKEND. $$ LEWITSKY