000 AXPZ20 KNHC 160227 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 218 UTC Thu May 16 2019 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 0300 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N83W to 1010 mb low pressure near 09N100W to 05N115W. The intertropical convergence zone from 05N115W to 05N140W. Scattered moderate convection is observed from 05N to 10N between 85W and 100W, and within 75 nm either side of line between 100W and 115W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Recent observations continue to indicate moderate to fresh NW winds off the coast of Baja California Norte, on the periphery of 1017 mb high pressure centered near 23N123W. Farther south, satellite imagery shows areas of smoke off the Mexican coast between Manzanillo and the Gulf of Tehuantepec. For the forecast, fresh to occasionally strong westerly gap winds will pulse over the northern Gulf of California overnight ahead of a cold front approaching the area from the west. Fresh to strong winds will also briefly follow the front over the northern Gulf of California late Thu as well. Long period swell will also follow the front off the coast of Baja California north of Cabo San Lazaro. Farther south, smoke will continue to impact visibility along the coast between Manzanillo and the Gulf of Tehuantepec. Looking ahead, another front will move across Baja California through early next week. Today was the first day of the Eastern North Pacific Hurricane Season. No tropical cyclone activity is expected for the next several days in the Mexican Offshore Waters. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A weak pressure pattern will maintain generally quiet wind conditions across the region through the forecast period, with generally onshore wind flow expected from the Papagayo region eastward through Fri night. Long period southwest swell will build seas to 8 ft west of Ecuador beginning on Fri night through early next week. Agricultural fires continue over northern Central America. However, the low-level southerly flow is generally keeping the associated smoke over land and no significant impact on visibility is occurring over the offshore waters at this time. REMAINDER OF THE AREA... A cold front from 30N125W to 25N140W will move across the waters north of 22N tonight and Thu. Weak 1017 mb high pressure is centered near 23N123W will dissipate through early Thu ahead of the advancing cold front. Scatterometer and altimeter satellite passes show moderate winds and seas less than 8 ft south of 30N near the front. The front is moving eastward across the waters north of 20N, disrupting the standard subtropical ridge over the area. This is maintaining fairly light trade winds farther south into the deep tropics. High pressure will build over the waters north of 25N through Fri, allowing trade winds farther south to increase to 15 to 20 kt west of 130W. Northerly swell in excess of 8 ft will also follow the front over waters north of 25N east of 120W Thu into Fri. The high pressure will drift east Sat and Sun ahead of another cold front entering the region from the northwest late Sat. This second front will move across the waters north of 20N through early next week, followed by long period NW swell of 8 to 9 ft. Looking ahead, high pressure will follow the second front Sun into Mon, supporting fresh trades farther south into the tropics. Seas will build to 8 ft from 10N to 20N west of 135W in mixed NW swell and shorter period NE wind waves. $$ Christensen