000 AXPZ20 KNHC 220239 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sat Apr 22 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 0000 UTC surface analysis and satellite imagery through 0230 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 07N83W to 06N90W to 05N100W. The ITCZ extends from 07N116W to 04N130W to 04N140W. Scattered moderate isolated strong convection is observed within 120 nm either side of the itcz between 118W and 135W. Scattered moderate convection was noted within 90-120 nm either side of the trough between 95W and 99W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge axis extends from a weakening 1021 MB high near 29N130W southeast through 24N120W to 18N105W. Earlier ASCAT scatterometer passes showed fresh northwesterly winds north of 27N, which are expected to diminish to moderate overnight. Associated seas of 8 to locally 11 FT will subside to 5-7 FT by late Saturday. Large NW swell will reach 29N120W on Sunday and spread southward across the waters north of 25N by late Monday then subside. A tightening pressure gradient will produce strong NW winds in waters north of 29N east of 122W on Tuesday. Gulf of California: Gentle NW flow is expected for most of the gulf through Saturday, except for variable winds setting up around a surface low north of 30N Saturday night and Sunday. Fresh to locally strong nocturnal SW winds are expected near 30N114W each night from Sunday through Tuesday. Gulf of Tehuantepec: Another gap wind event is expected to begin overnight Sun with winds rapidly increasing to 30 KT by sunrise Monday, then quickly diminishing later Monday. Blended NWP gridded forecasts show winds just below gale force with seas building to 10-11 FT. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Light to gentle winds in mostly onshore flow is expected during the day, becoming offshore at night. Combined seas of 3 to 5 FT in mixed SW and NW swell will prevail for the next several days. REMAINDER OF THE AREA... A surface ridge along about 130W continues to block the eastern advance of cold fronts. The latest cold front currently along 30N136W to 27N140W is forecast to move east and weaken through Sat. By late Sat the front will stall from roughly 30N130W to 25N140W then dissipate Saturday night or early Sunday. Large NW swell associated with the front will build seas of 8 to 12 FT in NW waters through early Sunday. Expect the NW swell to propagate east, reaching from the northern Baja Peninsula to 07N140W Sunday, and then quickly subside early next week. Strong NW winds are expected N of 28N east of 124W by the middle of next week. $$ COBB