000 AXPZ20 KNHC 110235 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0235 UTC Thu Apr 11 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 0230 UTC. ...SPECIAL FEATURES... Gulf of California Gale Warning: Fresh to strong NW winds prevail over the central and southern Gulf of California as strong high pressure builds into the region from the NW. Winds will briefly diminish across the Gulf on Thu. SW to W gap winds are expected to strengthen to gale force Thu night over the northern Gulf from 29.5N to 30.5N due to funneling through Baja California Norte. These winds will quickly subside below gale force on Fri morning. Please see the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 07N78W to 06N85W to 07N94W. The ITCZ extends from 07N94W to 08N120W to 05N140W. Scattered moderate convection is noted from 04N to 07N between 80W and 87W, and within 240 nm north of the ITCZ west of 135W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Strong 1042 mb high pressure NW of the region maintains a broad ridge extending SE along the outer Baja California offshore waters to the Revillagigedo Islands. Earlier scatterometer data showed fresh to locally strong winds north of Cabo San Lazaro over the Baja California Sur offshore waters with 10-15 ft seas per 18Z altimeter data. Another northerly surge over the northern waters beginning Thu night will result in fresh winds north of Cabo San Lazaro through Fri night. Strong to near gale force winds north of Punta Eugenia on Thu night and Fri will build seas to 16 ft. Wind speeds will diminish this weekend as high pressure weakens and moves westward. Elsewhere, long period NW swell across much of the region west of 100W will gradually decay through late week. Gulf of California: Please see the Special Features section above for information about the gale warning in effect for the northern Gulf of California Thu night. Gulf of Tehuantepec: Gentle to moderate onshore winds will prevail across the Gulf of Tehuantepec region through Sun. Looking ahead, the next Gulf of Tehuantepec gap wind event is expected late Sun night into Mon as strong to near gale force N winds develop over the Gulf. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Light to moderate, generally onshore winds will prevail across the Gulf of Papagayo region and adjacent offshore waters through Thu night before turning offshore Fri through Sun night. Seas in the 4-6 ft range will gradually subside to 3-5 ft over the weekend. Fresh to strong NE to E winds are expected across the Gulf Mon and Mon night as high pressure builds north of the area. Gulf of Panama: Light to gentle breezes will prevail across the Gulf of Panama region through Mon. Seas will generally remain in the 4-6 ft range through Fri night in SW swell, then subside to 3-5 ft this weekend. Elsewhere, light to gentle winds will persist through the week. Wave heights between Ecuador and the Galapagos Islands will generally remain 5-7 ft through Fri in long period SW swell. Further offshore, seas will peak around 8 ft tonight through Fri night over the waters SW of the Galapagos Islands. REMAINDER OF THE AREA... A strong high pressure ridge extends across the northern waters from 1042 mb high pressure centered NW of the region. Earlier scatterometer data showed a broad area of strong NE breezes with peak winds to 30 kt within the tight pressure gradient generally north of 20N and west of 120W. The strong winds have likely since expanded southward to roughly 18N. Elsewhere, fresh trade winds prevail south of the ridge to near the ITCZ. A 20Z altimeter pass over the far western portion showed seas as high as 15 ft within the area of 25-30 kt winds. A tight pressure gradient will prevail over the northern waters through Thu night as strong high pressure persists north of the region. A large area of fresh to strong N to NE winds will persist across the northern waters through Fri before diminishing Fri night through the weekend. Seas will remain 12 ft or greater west of 130W through Thu as NE wind waves mix with S and NW swell. A northerly surge Thu night into Fri will reinforce strong NW winds off Baja California Norte with seas building to around 16 ft. Long period NW swell maintains a band of 8-10 ft seas across much of the high seas from roughly 06N to 15N west of 105W. East of 120W, wave heights will gradually subside through late week as this swell decays over the region. Elsewhere, earlier altimeter data showed a region of 8-9 ft seas south of the Equator and west of 110W in mixed SW and NW swell. Seas of 8-9 ft will likely persist over the far southern waters through the weekend in mixed SW and NW swell. $$ Reinhart