000 AXPZ20 KNHC 110931 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 839 UTC Wed Mar 11 2020 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 0930 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: The gradient between high pressure over the Gulf of Mexico and low pressure over the tropical eastern Pacific will continue to cause N gales over the Gulf of Tehuantepec through this morning. Unfortunately, no wind or wave observations were available in the Gulf this evening. It is suspected that peak winds were around 35 kt and peak seas to 13 ft in mixed N wind waves and S to SW swell. As the pressure gradient diminishes, these gap winds will terminate by Thu afternoon. Seas generated by these northerlies will propagate well downstream of the Tehuantepec region through Thu. Tranquil conditions should be occurring over the Gulf by Thu night through at least Sun night. For more information 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 trough axis extends from 07N83W to 03N93W. From that point, the ITCZ continues to 05N129W. It is interrupted by a trough that extends from 11N129W to 03N132W. The ITCZ resumes at 07N136W to beyond 06N140W. No significant convection is occurring in association to the ITCZ. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details on a gale-force gap wind event in the Tehuantepec region. A cold front has reached Baja California Norte. It is expected to weaken as it moves across the northern waters today and Thu and then dissipate by Thu night. Southwest winds will increase to fresh to strong over the northern Gulf of California ahead of another cold front Thu night and Fri. Tranquil conditions should be occurring over all of the waters from Fri night through at least Sun night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The gradient between high pressure over Central America and lower pressure over the tropical eastern Pacific continues to result in fresh to locally strong NE winds over the Gulf of Papagayo. These winds will generally continue for the next several days. Peak seas will reach near 9 ft in mixed NE wind waves and S swell today, slightly subsiding Thu night through Fri night. No large SW swell is anticipated for the Central American and equatorial Pacific zones during the next several days. REMAINDER OF THE AREA... A 1014 mb low is centered near 30N125W with a trough trailing southwestward to 23N132W. Peak N winds behind the trough were up to 25 kt, according to the latest scatterometer observation. Peak seas near the 25 kt winds are near 12 ft. These winds will weaken later today, while the low moves southeastward to 27N122W by Thu afternoon, then dissipating by Fri afternoon. A large plume of moisture in the upper-troposphere is being advected northeastward from the ITCZ, reaching Baja California and causing widely scattered showers and thunderstorms. With the Pacific high displaced to 39N141W, the pressure gradient equatorward is rather weak and the NE trades are lighter - only gentle to fresh breeze - than usual. Little change in the trades are expected for the next several days. Peak seas in the trades west of 120W are near 10 ft due to NE wind waves and NW swell. The swell will relax during the next couple days, so combined seas will diminish below 8 ft by Fri. Farther east, a large area of 8-9 ft wave heights persists from roughly 05N to 12N between 93W and 115W from a mix of S swell and shorter period NE to E swell originating from gap wind events in the Gulfs of Tehuantepec and Papagayo. This will diminish below 8 ft by Thu. $$ Landsea