000 AXPZ20 KNHC 240920 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Jan 24 2023 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 0600 UTC surface analysis and satellite imagery through 0900 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: High pressure will build across the eastern slopes of the Sierra Madre Mountains in Mexico on Wed. This will support gale force winds across the Tehuantepec region Wed night through Sat morning. Winds will peak around 40 kt on Thu and into Thu night. Seas will peak near 16-17 ft on Thu night and Fri. This gap wind event will produce a swath fresh to strong winds and 8 ft seas or greater that will propagate well SW of the Tehuantepec region and reach beyond 100W by Thu night. Conditions will slowly improve on Sat into Sun. Please read the latest NWS High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from the coast of Panama near 08N78W to 03N88W. The ITCZ extends from 03N88W to 05N107W to 06N123W. A low pres is centered near 07N126W 1010 mb and a trough from 09N120W to 11N118W. The ITCZ continues from 05N128W to beyond 02N140W. Scattered moderate isolated strong convection is noted from 06N to 13N between 118W to 127W. Scattered moderate convection is noted from 03N to 07N and E of 85W and from 02N to 07N between 111W and 135W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section for information on the gale warning in the Gulf of Tehuantepec. A strong 1035 mb high pres is centered well northwest of the area. Meanwhile, a cold front is moving southward over the Baja California offshore waters and the southern Gulf of California. Moderate to locally fresh N to NE winds prevail over the Baja California Norte offshore waters with seas to 9 ft. Light to gentle winds are noted over the Baja California Sur offshore waters with 5-7 ft seas. In the Gulf of California, moderate to locally fresh winds are noted in the northern Gulf with fresh to strong winds in the central and southern Gulf. Seas are 3-5 ft with the highest in the central Gulf. Light to gentle winds continue over the southwest and southern Mexico offshore waters. Fresh to strong winds are prevailing over the Gulf of Tehuantepec and is expected to diminish over the next few hours. Seas range 4-6 ft over the southwest and southern Mexico offshore waters. For the forecast, a cold front will weaken over Baja California Sur and the southern Gulf of California today. Moderate winds will prevail over the Baja California offshore waters through Wed. Winds will increase fresh to strong on Thu as high pressure builds over the U.S. Great Basin. Fresh winds will continue across the Gulf of California through today with fresh to strong northerly winds occurring tonight through Fri. Conditions over Baja California and the Gulf of California will improve later on Fri and through the weekend. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong easterly gap winds prevail over the waters of the Gulf of Papagayo. Overnight scatterometer data confirmed these winds. Seas are 6-7 ft in this area. Moderate N winds are noted in the Gulf of Panama. Light to gentle winds prevail across the rest of the offshore waters with seas of 3-5 ft in mixed swell. For the forecast, fresh to strong NE winds will pulse nightly in the Gulf of Papagayo. Seas will build to near 7 ft tonight and 8-11 ft Thu night through Sat night. Meanwhile, seas will build to near 12 ft by Fri in the Guatemala and El Salvador offshore waters as swell from the Gulf of Tehuantepec expands into this area. A SW swell event will build seas to 7 ft from offshore Ecuador to the Galapagos Islands through Wed night. Elsewhere, light to gentle winds are forecast with seas of 3-5 ft. REMAINDER OF THE AREA... NW swell area is moving into the NW waters. The 12 ft seas extends N of 14N and W of 127W with altimeter overnight confirming seas peaking at 17 ft. Meanwhile, the pressure gradient between the 1035 mb high pressure near 39N136W and lower pressures in the deep tropics supports moderate to fresh easterly winds N of the ITCZ to 31N and west of 115W. The mixed swell found in these waters is producing seas of 8-11 ft. Gentle to moderate southerly winds are occurring south of the ITCZ. Seas are 5-8 ft in the waters described. For the forecast, the set of NW swell will continue progressing southeastward in the NW waters and reach as far south as the Equator and as far east as 100W through Fri. The swell will begin to subside by Sat. The fresh tradewinds will diminish later today. $$ AReinhart