000 AXPZ20 KNHC 250902 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Thu May 25 2017 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 0800 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The Monsoon Trough extends from 09.5N76W TO 08N83W TO 15N95W TO 13N103W TO 08N117W TO 09N129W. The ITCZ extends from 09N129W TO beyond 07N140W. Widely scattered moderate to strong convection is noted from 05N to 10N between 84W and 93W. Scattered to numerous moderate to strong convection is noted from 09N to beyond 18N between 94W and 106W. Widely scattered to scattered moderate isolated strong convection is noted within 90 nm N and 150 nm S of axis between 113W and 135W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A weak high pressure ridge snakes into the area from the NW and then W along about 25N, with the associated gradient supporting generally moderate northwest winds across the Baja California Peninsula waters. Light to gentle NW to N winds are noted elsewhere over the Mexican offshore waters to Acapulco. Seas are in the 4 to 5 ft range in mixed SW and NW swell across these waters, with slightly higher seas of 5 to 6 ft south of Puerto Angel. The pressure gradient will tighten slightly to the north of 20N through Friday as the ridge builds modestly into the region, with winds and seas increasing slightly. Gentle to moderate SE winds occurring between Tehuantepec and offshore of Acapulco will gradually weaken and veer SW to W through Friday. Very active moderate to strong convection occuring across the waters from the Tehuantpec region SW to well offshore along 106W will shift slowly westward during the next 24 hours. Expect frequent lighting, strong gusty winds, and seas 6-9 ft to accompany this weather. In the Gulf of California, mainly light to gentle variable winds are expected through Thursday except in the northern Gulf, with seas of 2 ft or less, except 3 to 5 ft near the entrance to the Gulf. Low pressure is presently deepening rapidly just to the north of the area over SW Arizona, and should remain below normal through at least Thursday night. A trough will extend from the low across the northern Gulf to Baja California Norte through Friday. Fresh to strong southwest to west have developed to the southeast of the trough tonight, and will do so again on Thursday night into Friday as winds become enhanced through the gaps in the higher terrain of Baja. Winds gusts could reach 30 kt downstream of the gaps. Seas are expected to build to 6-8 ft each night during the nocturnal wind max. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle SW to W winds prevail between the Papagayo region and Tehuantepec, with seas of 4 to 5 ft in SW swell. Expect NW to W monsoonal winds to spread across the coastal waters through Friday as an early season tropical wave moves into the eastern Pacific today through Friday. Nocturnal offshore winds will pulse to fresh levels near the Gulf of Papagayo by Saturday night, behind the wave, and again on Sunday night. Moderate SW winds will continue to the south of 09N through Thursday night. A new pulse of SW swell is forecast to arrive Thursday through late Friday. Otherwise, little change is anticipated through the upcoming weekend. REMAINDER OF THE AREA... A weak ridge extends from 30N140W southeastward to near 23N132W and then eastward to near 26N117W. the ridge will slowly shift SE Friday through Saturday as a weak frontal boundary sinks southward into the northern waters between 120W and 140W. Moderate northerly winds will follow the front into the northern waters, with long period N swell producing max seas of 7 to 9 ft across the area from 30N to 32N between 125W and 135W today, before subsiding to less than 8 ft Friday afternoon. Elsewhere N of the deep tropics, the weak ridge will maintain moderate trade winds S of 18N, with seas of 5 to 7 ft expected through Friday. $$ Stripling