000 AXPZ20 KNHC 281555 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC THU JAN 28 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 GALE WARNING...A VERY TIGHT PRES GRADIENT HAS SETTLED IN ACROSS SOUTHEASTERN MEXICO AND THE ISTHMUS OF TEHUANTEPEC IN ASSOCIATION WITH A 1028 MB HIGH CENTER LOCATED OVER NE MEXICO. THIS WEATHER PATTERN HAS INITIATED A GALE WIND EVENT OF N-NE 30-35 KT WINDS THROUGH THE GULF. THIS MORNING... VISIBLE SATELLITE IMAGERY REVEALS A ROPE CLOUD MOVING DOWNSTREAM OF THE GULF WHICH LIKELY DELINEATES THE LEADING EDGE OF THE CURRENT GAP WIND EVENT. WINDS ARE EXPECTED TO INCREASE TO 30-40 KT EARLY THIS AFTERNOON AS THE THE PRESS GRADIENT TIGHTENS FURTHER AND CONTINUE INTO LATE FRI MORNING. SEAS OF 9-14 FT WILL BUILD TO 10-16 FT BY LATE TONIGHT. THE TIGHT PRES GRADIENT WILL BEGIN TO WEAKEN FRI AFTERNOON ALLOWING FOR THE GALE WINDS TO DIMINISH TO 30-35 KT...AND TO JUST BELOW GALE FORCE BY EARLY FRI EVENING. THIS GAP WIND EVENT WILL PERSIST THROUGH LATE SAT MORNING. SEAS ARE FORECAST TO SUBSIDE TO 8-10 FT BY EARLY FRI EVENING. NE SWELL RESULTING FROM THIS EVENT WILL SPREAD SW AWAY FROM THE TEHUANTEPEC REGION...AND MIX WITH LONG PERIOD NW SWELL OVER AN AREA FROM 09N TO 14N BETWEEN 94W AND 102W BY EARLY FRI MORNING...AND FROM 07N TO 14N BETWEEN 94W AND 105W BY FRI NIGHT. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE ITCZ AXIS EXTENDS FROM 06N89W TO 06N99W...THEN RESUMES AT 05N103W TO 04N110W TO 05N120W TO 04N125W TO BEYOND 05N140W. SCATTERED MODERATE CONVECTION IS NOTED FROM 04N TO 06N BETWEEN 105W AND 109W...FROM 06N TO 08N BETWEEN 115W AND 118W...AND WITHIN 60 NM S OF AXIS W OF 137W. ...DISCUSSION... A 1028 MB HIGH CENTERED AT 30N130W HAS A RIDGE AXIS EXTENDING SE TO NEAR THE REVILLAGIGEDO ISLANDS...AND ANOTHER RIDGE EXTENDING SW TO BEYOND THE AREA AT 27N140W. THIS HIGH IS FORECAST TO MOVE SLIGHTLY SW OVER THE NEXT 24 HOURS WHILE WEAKENING A LITTLE. THE PRES GRADIENT BETWEEN THE RIDGE AND LOWER PRES IN THE VICINITY OF THE ITCZ HAS INCREASED SINCE YESTERDAY ALLOWING FOR AN AREA OF FRESH TO STRONG TRADE WINDS TO MATERIALIZE FROM 07N TO 12N W OF 128W BASED ON RECENT SCATTEROMETER PASSES. SEAS WITHIN THIS AREA ARE IN THE 9-12 FT RANGE. THE GRADIENT IS FORECAST TO GRADUALLY LOOSEN UP THROUGH FRI EVENING AS THE HIGH SHIFTS MORE TO THE SW AND WEAKENS SOME MORE. AS A RESULT... THE AERIAL EXTENT AND STRENGTH WILL DIMINISH IN ABOUT 24-36 HOURS. A PERSISTENT WEAK SURFACE TROUGH IS ANALYZED FROM 11N98W TO 04N101W. SCATTERED MODERATE CONVECTION IS NOTED NEAR THE NORTHERN END OF THE TROUGH AXIS FROM 08N TO 09.5N BETWEEN 98W AND 100W. ANOTHER WEAK TROUGH IS EMBEDDED WITHIN THE ITCZ AND EXTENDS FROM 08N132W TO 03N134W. ONLY A FEW SHOWERS ARE SEEN NEAR THE TROUGH AXIS. A LARGE LONG PERIOD NW SWELL WITH WAVE PERIODS OF 19-21 SECONDS WILL CONTINUE TO PROPAGATE TO THE SE ACROSS THE WATERS W OF 100W THROUGH THE REMAINDER OF THE WEEK. ADDITIONAL PULSES OF NW SWELL ARE CURRENTLY REACHING THE FAR NW CORNER OF THE AREA BUILDING SEAS UP TO 19 FT. THE LEADING EDGE OF THIS SWELL EVENT PRESENTLY EXTENDS FROM THE COAST OF GUERRERO JUST W OF ACAPULCO TO SOUTH OF THE EQUATOR NEAR 05S120W. ROUGH WAVE ACTION PRODUCING HAZARDOUS SURF CONDITIONS CAN BE EXPECTED ALONG THE PACIFIC COAST OF BAJA CALIFORNIA FRI THROUGH SUN AS THE SECOND SET OF NW SWELL ARRIVES. THESE CONDITIONS WILL REACH THE REVILLAGIGEDO AND LAS MARIAS ISLANDS ON SAT. GAP WINDS... GULF OF CALIFORNIA...THE STRONG NW WINDS ARE CONFINED TO S OF 28N. THESE WINDS WILL GRADUALLY DIMINISH TO MAINLY FRESH INTENSITY BY EARLY THIS AFTERNOON AS THE PRES GRADIENT BETWEEN STRONG HIGH PRES OVER THE U.S. GREAT BASIN AND SURFACE TROUGHING OVER NW MEXICO SLACKENS. SIMILAR STRONG NW-N WINDS WITH SEAS OF 8 FT ARE OVER THE ENTRANCE TO GULF...S TO NEAR 19N AND BETWEEN 106W-109W. THESE WINDS WILL LINGER INTO EARLY THIS AFTERNOON BEFORE DIMINISHING TO A MODERATE RANGE. AN EARLIER ASCAT PASS INDICATED FRESH NORTHERLY WINDS NEAR CABO CORRIENTES. GULF OF PAPAGAYO...STRONG NE WINDS ARE FORECAST TO START UP AGAIN FRI MORNING AS HIGH PRES SURGING SOUTHWARD ACROSS THE NORTHERN PORTION OF CENTRAL AMERICA INTERACTS WITH LOWER PRES TO ITS S OVER THE REMAINDER OF CENTRAL AMERICA AND FAR EASTERN PACIFIC WATERS. THESE WINDS WILL INCREASE TO 25-30 KT FRI NIGHT INTO SAT AND SPREAD SW N TO NEAR 11.5N AND W TO NEAR 88W AS THE GRADIENT TIGHTEN FURTHER. SEAS WITHIN THE AREA OF WINDS ARE FORECAST TO BUILD TO 10 FT AT THAT TIME. IN ADDITION NE-E WINDS IN THE 20-25 KT RANGE ARE EXPECTED TO EXTEND DOWNWIND OF THE GULF TO COVER ROUGHLY THE WATERS FROM 08N TO 10N BETWEEN 88W AND 92W. GULF OF PANAMA...FRESH TO STRONG NORTHERLY WINDS ARE EXPECTED TO FUNNEL INTO THE GULF OF PANAMA FROM THE CARIBBEAN SEA LATE FRI NIGHT INTO EARLY SAT MORNING. SEAS ARE FORECAST TO BUILD TO AROUND 8 FT. $$ GR