000 AXPZ20 KNHC 190949 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0900 UTC. ...SPECIAL FEATURE... GULF OF TEHUANTEPEC GALE WARNING...THE 0516 UTC HIGH RESOLUTION RAPIDSCAT SHOWED NORTHERLY WINDS OF 35-50 KT ACROSS THE GULF AND STORM WARNING WAS ISSUED WITH THE 0600 UTC FORECAST PACKAGE. AN EARLIER ALTIMETER PASS INDICATED SEA HEIGHTS UP TO 12 FT. THESE STORM WINDS ARE ASSOCIATED WITH A REINFORCING PUSH OF COLD AIR ACROSS THE GULF OF MEXICO AND THE MEXICO COASTAL PLAINS INTO SOUTH-CENTRAL MEXICO. SEAS ARE EXPECTED TO BUILD UP TO 16-17 FT WITH THE STRONGEST WINDS. THIS GALE WIND EVENT SHOULD PERSIST THROUGH WED MORNING...BUT WINDS ARE FORECAST TO DIMINISH TO MINIMAL GALE FORCE BY THIS AFTERNOON. 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...CURRENTLY...SCATTEROMETER DATA INDICATE NE WINDS OF 30-35 KT EXTENDING DOWNWIND OF THE GULF AND WITHIN 30 NM OF A LINE FROM 11N86W TO 10N88W. FRESH TO STRONG WINDS ARE ALSO NOTED OVER LAKE NICARAGUA AND FROM 09N TO 12N E OF 89W. EXPECT BUILDING SEAS OF 8-12 FT DOWNSTREAM OF THE GULF TO NEAR 92W/93W BY EARLY THIS MORNING. WINDS ARE FORECAST TO DIMINISH JUST BELOW GALE FORCE THIS AFTERNOON AND EVENING AND INCREASE AGAIN TO MINIMAL GALE FORCE LATE TONIGHT INTO WED MORNING. THE RESULTANT NE SWELL WILL IMMEDIATELY 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... THE ITCZ AXIS EXTENDS FROM 03N85W TO 04N100W TO 06N110W TO 03N120W TO 03N140W. SCATTERED MODERATE CONVECTION IS WITHIN 90 NM N OF AXIS BETWEEN 88W AND 90W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED ON EITHER SIDE OF THE AXIS...BUT MAINLY FROM 02N TO 04N BETWEEN 128W AND 137W. ...DISCUSSION... A HIGH RESOLUTION RAPIDSCAT PROVIDE OBSERVATIONS OF NORTHERLY WINDS IN THE 20-30 KT RANGE ACROSS THE GULF OF PANAMA AND DOWNSTREAM TO NEAR 04N/05N. EXPECT BUILDING SEAS OF 8-11 FT WITH THESE WINDS BY THIS AFTERNOON. 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 RELAXES A BIT. A 1024 MB HIGH PRES IS CENTERED NEAR 29N125W WITH A RIDGE AXIS EXTENDING SE TO NEAR THE REVILLAGIGEDO ISLANDS. THE PRESSURE GRADIENT BETWEEN THIS AREA OF HIGH PRESSURE AND LOWER PRESSURE IN THE VICINITY OF THE ITCZ CONTINUES TO SUPPORT A BELT OF FRESH TO LOCALLY STRONG TRADE WINDS...PARTICULARLY FROM 05N TO 15N W OF 125W. THE HIGH PRESSURE WILL REMAIN QUASI STATIONARY OVER THE NEXT 24 HOURS...THEN MOVE NE TO A POSITION NEAR 31N124W BY WED EVENING AS A NEW COLD FRONT REACHES 30N140W. FRESH TO STRONG SOUTHERLY WINDS ARE EXPECTED AHEAD OF THE FRONT DUE TO THE PRES GRADIENT BETWEEN THE ABOVE MENTIONED RIDGE AND THE FRONT. MARINE GUIDANCE SUGGESTS S-SW WINDS IN THE 20-25 KT RANGE E OF FRONT TO A LINE FROM FROM 30N132W TO 27N136W TO 26N140W. ANOTHER SET OF LONG PERIOD NW SWELL WILL FOLLOW THE FRONT SPREADING SE ACROSS THE FORECAST 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. $$ GR