000 AXPZ20 KNHC 080239 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC WED APR 08 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0130 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE INTERTROPICAL CONVERGENCE ZONE AXIS WAS ANALYZED FROM 03N94W TO 05N105W TO 03N125W TO 03N140W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS N OF THE AXIS TO 09N W OF 133W. ...DISCUSSION... THE SUBTROPICAL HIGH IS BEING COMPROMISED BY A DISSIPATING COLD FRONT STRETCHING FROM NEAR SANTA BARBARA CALIFORNIA THROUGH 32N122W TO 30N130W. THE MAIN HIGH PRESSURE CENTER WAS ANALYZED NEAR 35N135W AT 1022 MB WITH A SECOND...PINCHED OFF...1019 MB HIGH S OF THE FRONT NEAR 27N129W. A WEAK RIDGE STRETCHES OVER THE FORECAST AREA FROM THE SECOND HIGH TO NEAR 13N98W. ASCAT DATA SHOWS TRADE WINDS OVER W WATERS ON THE SW SIDE OF THE RIDGE ARE A FRESH TO STRONG BREEZE FROM 06N-14NW OF 135W AND A MODERATE TO FRESH BREEZE ELSEWHERE. ALTIMETER DATA SHOWS SEAS TO AT LEAST 9 FT LIE WITHIN THE AREA OF FRESH TO STRONG TRADES. THE FRESH TO STRONG TRADES AND SEAS OVER 8 FT WILL SHIFT W OF THE AREA WED NIGHT. THE SECOND HIGH CENTER IS EXPECTED TO DISSIPATE BY WED EVENING WHILE THE MAIN SUBTROPICAL HIGH IS FORCED EASTWARD JUST N OF THE AREA BY AN APPROACHING COLD FRONT AND THEN SHIFTS S INTO THE FORECAST AREA...LYING NEAR 28N123W BY THE END OF THE FORECAST PERIOD THU EVENING. THE HIGH WILL REMAIN WEAK ENOUGH TO PREVENT TRADE WINDS FROM INCREASING AGAIN TO THE ADVISORY CRITERIA OF A FRESH TO STRONG BREEZE. MEANWHILE...MERGING NE...SW AND NW SWELL IN THE TRADE WIND ZONE IS SUPPORTING AN AREA OF SEAS TO 8 FT CENTERED WITHIN ABOUT 150 NM OF 10N120W THAT IS FORECAST TO MIGRATE W TO NEAR 11N129W THROUGH THU EVENING. THE COLD FRONT ENCROACHING ON THE SUBTROPICAL HIGH IS FORECAST TO REACH THE NW FORECAST WATERS THU. WINDS ARE EXPECTED TO BE JUST BELOW ADVISORY CRITERIA BOTH AHEAD OF AND BEHIND THE FRONT...AND SEAS OVER 8 FT IN NW SWELL WILL BE CONFINED N OF 30N THROUGH THU EVENING. ALOFT...SPLIT FLOW OVER THE CENTRAL PACIFIC HAS DIRECTED A SOUTHWESTERLY JET ACROSS THE AREA FROM 15N140W TO THE NORTHERN GULF OF CALIFORNIA. THIS JET IS PROPELLING TROPICAL MOISTURE ALOFT ACROSS THE FORECAST AREA. MULTI-LEVEL CLOUDINESS WITH SOME EMBEDDED SHOWERS CAN PRIMARILY BE FOUND WITHIN 300 NM EITHER SIDE OF A LINE FROM 10N129W TO MAZATLAN. THIS PATTERN IS EXPECTED TO CHANGE LITTLE OVER THE NEXT TWO DAYS. GAP WINDS... GULF OF TEHUANTEPEC...A QUICK BURST OF N WINDS IS FORECAST IN THE GULF OF TEHUANTEPEC IN THE MORNING HOURS ON WED. THE PRESSURE GRADIENT BETWEEN A MERIDIONAL TROUGH OVER THE BAY OF CAMPECHE AND RIDGING TO ITS NW WILL FORCE N WINDS THROUGH CHIVELA PASS. THESE WINDS WILL BE ENHANCED BY NOCTURNAL DRAINAGE FLOW. WINDS ARE FORECAST TO REACH AS STRONG AS 30 KT WED MORNING BEFORE DIMINISHING MIDDAY. GULF OF PAPAGAYO...THE PRESSURE GRADIENT BETWEEN RIDGING OVER THE NW CARIBBEAN AND THE ITCZ TO THE SW IS SUPPORTED A FRESH TO STRONG NE BREEZE SEEN BY ASCAT AROUND 1600 UTC THAN HAS SINCE SHRUNK BACK NEAR THE COAST. NOCTURNAL DRAINAGE FLOW WILL ENHANCE THESE WINDS TO NEAR GALE FORCE EARLY WED. THE PRESSURE GRADIENT WILL WEAKEN THROUGH THE REMAINDER OF THE FORECAST PERIOD...WITH WINDS EXPECTED TO DIP BELOW THE ADVISORY CRITERIA BY THU AFTERNOON. GULF OF PANAMA...NEAR GALE FORCE TRADE WINDS IN THE CARIBBEAN ALONG THE COAST OF COLOMBIA ARE SIPHONING INTO THE GULF OF PANAMA BELIEVED TO BE A FRESH TO STRONG N BREEZE THIS EVENING. THESE WINDS WILL SHIFT S-SW AWAY FROM THE GULF OF PANAMA TONIGHT AS THE LOW OVER N COLOMBIA SHIFTS W ALONG WITH THE TIGHTEST PRESSURE GRADIENT THE WINDS WILL DIMINISH BELOW ADVISORY CRITERIA BY SUNRISE WED. $$ SCHAUER