000 AXPZ20 KNHC 051550 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Sat May 5 2018 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: Fresh to locally strong northerly winds will gradually increase to strong to near gale force this evening, with these conditions continuing through Sun. The northerly drainage flow is forecast to increase to minimal gale force on Sun evening, with seas building to 12 ft downstream near 15N 95.5W. The pressure gradient will relax on Mon with near gale winds continuing through early Tue morning. The gap wind event should end by late Wed morning. A gale warning is in effect. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 08N78W to 06N94W to 07N110W. The ITCZ continues from 07N110W to 04N125W to 06N140W. A cluster of moderate to isolated strong convection is within about 180 nm S of trough between 88W and 92W. Scattered moderate convection is from 04N to 08N between 82W and 87W, from 10N to 13N between 107W and 111W, and from 08N to 10N between 121W and 126W. Another cluster of moderate to isolated strong convection is from 12N to 15N between 91W and 95W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Refer to special features section for a warning in the Gulf of Tehuantepec. High pressure of 1022 mb located over the north-central forecast waters near 29N130W extends a ridge SE across the waters west of Baja California to near the Revillagigedo Islands. Gentle to moderate winds are expected across the offshore waters W of Baja California during the next several days. Gulf of California: Moderate northwest flow will continue across the gulf waters north of 30N through this afternoon, and moderate to locally fresh northwest flow are expected across the gulf waters south of 25N through this evening. Then light, mostly southerly flow forecast through the middle of next week except moderate nocturnal drainage flow near gap areas. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Moderate to locally fresh nocturnal winds are expected through the middle of next week. Gulf of Panama: Gentle northerly nocturnal flow is forecast through the middle of next week. REMAINDER OF THE AREA... A surface high is centered near 32N127W with a ridge extending across the waters N of 15N W of 110W. The high will shift southeast today allowing a cold front to reach a position from 30N138W to 29N140W late this afternoon where it will stall and weaken. Another cold front will reach 30N140W Sun night, and extend from 30N135W to 25N140W by Mon night. Fresh to strong S-SW winds will precede the front affecting the waters N of 29N W of 137W Sun night into Mon morning. A new set of long period NW swell will follow the front, building seas to 14 or 15 ft near 30N140W by late Mon. Model guidance is hinting that a tropical low will develop near 11N115W during the middle of next week and intensify as it tracks northwest and later north. $$ GR