000 AXPZ20 KNHC 212202 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Sun Nov 21 2021 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 140W. The following information is based on satellite imagery, weather observations, radar, and meteorological analysis. Based on 1800 UTC surface analysis and satellite imagery through 2145 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A cold front will move across the Gulf of Mexico early next week. High pressure will build along eastern Mexico in the wake of the front. The tightening pressure gradient between this building high pressure and lower pressure within the eastern north Pacific monsoon trough will usher in the next gale-force gap wind event across the Gulf of Tehuantepec. Gale-force winds are forecast from Mon night through Tue before diminishing. Seas will peak to near 12 ft early Tue morning. Please see the latest NWS High Seas Forecast issued by the National Hurricane Center at website://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more information. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northwestern Colombia to across southern Costa Rica, then continues to 08N84W and to 07N108W, where latest scatterometer data indicates that it transitions to the ITCZ to 09N120W to 09N130W and to beyond the area at 08N140W. Scattered moderate to isolated strong convection is within 120 nm north of the ITCZ between 122W-125W and within 60 nm south of the ITCZ between 124W-127W. Scattered moderate convection is noted from 06N to 08N between 79W-84W, also within 180 nm north of the trough between 100W-108W and within 60 nm south of the trough between 103W-107W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO Please see above for more information on an upcoming gale-force gap wind event over the Gulf of Tehuantepec. The latest ASCAT pass over the Gulf of Tehuantepec region shows fresh to strong north winds across the Gulf of Tehuantepec. Seas there are to 8 ft. Gentle winds are noted elsewhere over the open waters off Mexico. Generally light and variable winds are over the Gulf of California, with the exception of the far northern section where fresh to strong northwest winds have developed along with seas up to 6 ft. Seas elsewhere across the Gulf are lower, in the 1-3 ft range. Seas are in the 4-5 ft range over the open waters off Mexico. For the forecast, the fresh to strong winds across the Gulf of Tehuantepec will increase to near gale-force by early on Mon and to gale-force Mon night into Tue as strong high pressure surges southward over eastern Mexico. The fresh to strong northwest winds over the northern Gulf of California will diminish to moderate speeds Mon afternoon, then redevelop late Mon night, and spread across the entire Gulf through Fri and begin to diminish Fri night. Moderate northwest to north winds are expected offshore Baja California Norte beginning Wed and continue through Fri and diminish slight Fri night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR Northeast winds have diminish to fresh speeds over the Gulf of Papagayo, with seas to 6 ft. Light to gentle winds are elsewhere north of the monsoon trough. Gentle to moderate winds prevail south of the monsoon trough. Seas are in the 4-5 ft in south to southwest swell. For the forecast, the northeast winds in the Papagayo region will once again pulse to strong speeds early Tue and diminish back to fresh speeds Tue afternoon. Gentle to moderate winds will prevail across the rest of the area for the next several days. REMAINDER OF THE AREA... Broad high pressure prevails over the northern waters. The pressure gradient between this are of high pressure and lower pressure in the vicinity of the ITCZ is supporting moderate to fresh northeast to east winds north of the ITCZ to near 22N and west of about 120W. Moderate north to northeast winds are north of 27N between 118W-134W. Gentle to moderate mainly northeast to east winds remain elsewhere. Seas of 6-8 ft continue in the area of fresh winds and 4-6 ft elsewhere, except for slightly higher seas of 5-7 ft on the fringes of the 6-8 ft seas. $$ Aguirre