000 AXPZ20 KNHC 032138 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Mon Jan 3 2022 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 2040 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec gale warning: Strong gales to 40 kt and seas as high as 19 ft will persist across and downstream of the Gulf of Tehuantepec through this evening. Strong high pressure is building behind a cold front that moved through the western Gulf of Mexico and southern Mexico Sun and Sun night. The resulting tight pressure gradient along with cold, dry air following the front is combining to deliver gale-force gap winds across the Gulf of Tehuantepec this afternoon, with gales expected to continue through Tue morning. Peak seas of 16-19 ft will prevail offshore today, before winds and seas gradually start to diminish tonight through Tue morning, then fall below gale force around midday Tue. The strong gales will generate a large plume of swell in excess of 8 ft extending as far as 700 nm downstream from the Gulf of Tehuantepec through mid week. For further details, please see the latest NWS High Seas Forecast issued by the National Hurricane Center, at the website: https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N74.5W to 05.5N95W. The ITCZ extends from 05.5N95W to 09N115W to beyond 09.5N140W. Scattered moderate isolated strong convection is noted from 07.5N to 18.5N between 119W and 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO Strong 1048 high pressure centered north of the area over the Great Basin continues to support fresh to strong winds over much of the central and southern portions of the Gulf of California, as verified by 16-1700 UTC scatterometer satellite data. Moderate to fresh N winds prevail across the northern Gulf, where seas are 3 to 6 ft. Seas of 6 to 8 ft prevail in the central and southern Gulf of California. Seas are 4 to 7 ft in NW swell elsewhere over open waters north of 20N. Farther south, gentle to moderate SE to E winds and seas of 3 to 5 ft are noted elsewhere south of 20N. For the forecast, gales to near 40 kt will persist across the Gulf of Tehuantepec region into late tonight, spreading large NE swell well beyond the outer offshore waters. Farther north, high pressure north of the area over the Great Basin will begin to shift eastward allowing winds inside the Gulf of California to diminish modestly, with fresh NW winds persisting over the central Gulf of California through Thu morning. Looking ahead, fresh to strong gap winds are expected again over the Gulf of Tehuantepec by Fri night as another cold front moves across the western Gulf of Mexico and through southern Mexico. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR Moderate NE gap winds prevail over the Gulf of Papagayo region and extend offshore to near 88W, with light to gentle winds elsewhere north of the monsoon trough. Moderate NW to N winds prevail over the northern Gulf of Panama, with gentle to moderate winds farther south and over the remainder of the waters south of the monsoon trough. Seas are in the 5-6 range across the Gulf of Papagayo, and 3-5 ft across the rest of the forecast waters. For the forecast, winds will increase across the Papagayo region by this evening as strong high pressure builds across the Gulf of Mexico and NW Caribbean. This will produce fresh to strong winds pulsing across the Papagayo region through Wed morning, with seas building to 8 ft. Light to gentle winds will occur elsewhere north of the monsoon trough, with gentle to moderate winds elsewhere south of the monsoon trough. A strong gale-force gap wind event across the Tehuantepec region will generate large NW swell to impact the Guatemala and El Salvador offshore waters late today through Tue night. Looking ahead, fresh to strong gap winds may again pulse across the Gulf of Papagayo by Fri. REMAINDER OF THE AREA 1027 mb high pressure is centered near 29N128W. A trough in the deep tropics is near 133W, near an area of showers and thunderstorms reaching from 07.5N to 18.5N between 120W and 132W. The surface trough along with the shower and thunderstorm activity is supported by an upper trough reaching from 21N136W to 10N126W. Scatterometer satellite data from 1700 and 1800 UTC showed fresh to strong winds between the trough and the high pressure, specifically from 14N and 23N between 124W and 140W, where seas are 8 to 10 ft in N swell. Elsewhere, gentle to moderate NE to E winds are evident north of 10N, with gentle to moderate SE to S winds elsewhere south of 10N, with 4 to 6 ft seas. For the forecast, high pressure will continue to support a broad area of fresh to locally strong trade winds from 10N to 25N and west of 120W through mid week, as the current surface trough moves westward across the tropics. Additional NW swell in excess of 8 ft will enter the waters north of 25N west of 120W tonight and Tue, and reinforce the earlier swell to create 8 to 11 ft seas over much of the area north of a line from Los Cabos to 05N140W by mid week. Farther east, swell generated from the gale event in the Gulf of Tehuantepec will bring mixed swell in excess of 8 ft east of 110W from 06N to 13N from late Mon into Wed. $$ Stripling