000 AXPZ20 KNHC 300306 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Tue Mar 30 2021 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 0300 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A cold front has stalled across the western Gulf of Mexico along 95W to the central Bay of Campeche today, and is aiding in producing strong northerly gap winds across and downstream of the Gulf of Tehuantepec this afternoon. However ASCAT satellite data from 1423 to 1632 UTC measured peak winds of only 30 kt during that period. Northerly gap winds across the Tehuantepec area have diminished below gale force a few hours before expected, and the gale warning has been discontinued. Winds near 30 kt and seas to 10 ft are expected to persist through the evening hours before winds and seas gradually diminish Tue, falling below 20 kt and 8 ft by late afternoon. Looking ahead, computer model guidance agrees on a second round of gales starting potentially early Thu morning and continuing into Sat of next weekend. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 07N78W to 06N90W. The ITCZ continues from 06N90W to 03N105W to 05N112W, and from 05N120W to beyond 05N140W. Scattered moderate to strong convection is noted from 05N to 08N between 115W and 125W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The strong to near-gale force gap winds in the Gulf of Tehuantepec this afternoon are starting to diminish as high pressure north of the area weakens. Seas are still reaching as high as 8 ft downstream of the Gulf of Tehuantepec with a component of longer-period SW swell. This swell is supporting 3 to 5 ft seas elsewhere off southern Mexico south of Cabo Corrientes, with light to gentle breezes. Farther north, gentle to moderate NW winds persist with 3 to 5 ft seas in open waters with mixed SW and NW swell. For the forecast, winds remain diminished but seas will build off Baja California late Tue through mid week due to new NW swell. Looking ahead, strong gales are possible again in the Gulf of Tehuantepec early Thu as another cold front moves into the region. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Observations from Liberia, Costa Rica show persistent fresh E winds, and indication that there are stronger offshore gap winds into the Gulf of Papagayo. Seas are likely reaching near 8 ft downstream of the plume of E gap winds, combining with a component of longer-period SW swell. Fresh N gap winds are also possible through the Gulf of Panama. Elsewhere light to gentle winds continue over the Central American offshore waters with 3-5 ft seas. For the forecast, fresh to strong offshore gap winds will persist across Gulf of Papagayo region, through the end of the week. Seas will build from northern Costa Rica to Guatemala later in the week, due to seas generated from the Papagayo and Tehuantepec gap wind areas mixing with longer period SW swell. REMAINDER OF THE AREA... An upper low remains anchored near 25N128W. Moisture levels have been increasing in the divergent deep layer southerly flow east of the upper low is supporting clusters of thunderstorms from 23N to 27N between 122W and 127W. This mid to upper level pattern is also supporting a surface trough farther south into the deep tropics, from 04N120W to 08N114W. This is supporting an area of moderate to fresh trade winds to the west of the trough, with clusters of showers and thunderstorms north of the ITCZ. A scatterometer satellite pass indicated a large area of fresh trade winds farther west, extending from 05N to 15N west of 130W. This area is south of 1045 mb high pressure centered near 47N142W. Seas are 8 to 9 ft in these areas of trade winds, assisted by a component of SW swell. Farther east in the deep tropics, gentle to moderate winds are noted with 4 to 6 ft in SW swell. Large N swell accompanying the front will reach as far south as 25N between 118W and 135W by mid week, then subsiding through late week. Farther east, seas will build to at least 8 ft from 05N to 10N between 95W and 110W due to east swell generated from gap wind flow and persistent longer period SW swell. $$ Christensen