000 AXPZ20 KNHC 151515 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1515 UTC Mon Apr 15 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Gale force northerly gap winds are likely ongoing this morning over the Gulf of Tehuantepec with a high pressure ridge situated across the western Gulf of Mexico. Max significant wave heights were analyzed to 13 ft at 12Z in this region. Winds over the Gulf of Tehuantepec will diminish below gale force by this afternoon and continue weakening tonight into Tue as high pressure over the Gulf of Mexico shifts eastward. A strong cold front crossing the Gulf of Mexico later in the week could result in another gale event in the Gulf of Tehuantepec by Fri night. Please read 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 07N80W to 05N95W to 07N110W to 06N121W. The ITCZ continues from 06N121W to 07N130W to beyond 05N140W. Scattered moderate and isolated strong convection is noted from 04N to 09N east of 91W. Scattered moderate convection is present within 120 nm north of the trough between 105W and 111W and from 05N to 07.5N west of 131W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A high pressure ridge persists west of the Baja California offshore waters. Overnight scatterometer data showed light to gentle NW breezes off the Baja California coast. Expect moderate to fresh winds Tue through Wed across the waters north of Cabo San Lazaro as a weakening cold front or trough crosses the area. Seas will likely build to 8 ft during this period as the offshore winds strengthen. Otherwise, gentle to moderate winds will prevail off the Baja Peninsula through Fri night. Gulf of California: Fresh to strong SW to W gap winds will develop north of 29.5N tonight into Tue. A weakening cold front or trough will approach the northern Gulf late Tue and Tue night, which will likely support another brief gap wind event Tue night with fresh to locally strong winds expected. Gulf of Tehuantepec: Please see the Special Features section above for more information on the gale warning in effect. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh to strong NE to E winds will pulse over the Gulf of Papagayo region through Wed. The strongest winds will occur during the overnight and early morning hours. Each pulse of strong winds will build seas to 8 ft downstream of the Gulf. Gulf of Panama: Gentle to moderate winds are expected across the Gulf of Panama through Tue. Winds will strengthen to moderate to fresh speeds Tue night and Wed as high pressure builds north of the region. Seas will build to 5-7 ft by midweek as SW swell combines with increasing wind waves. Elsewhere, generally light to moderate winds will prevail over the waters west of Ecuador through Fri night. Wave heights between Ecuador and the Galapagos Islands will remain in the 5-7 ft range in SW swell for much of the week. Further offshore, expect 6-8 ft seas SW of the Galapagos Islands by tonight. REMAINDER OF THE AREA... A ridge extends across the northern forecast waters from high pressure centered north of the Hawaiian Islands. Overnight scatterometer data showed moderate NE winds south of this ridge, generally north of 20N and west of 135W. Further south, another area of moderate NE winds was shown north of the ITCZ. Expect fresh to strong trade winds Tue through Wed as the pressure gradient tightens in response to a surface trough developing in the vicinity of 120W. Cross equatorial SW swell will help maintain 8 ft seas generally south of 02S and west of 105W through tonight. $$ Reinhart