000 AXPZ20 KNHC 021532 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu Feb 2 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 1200 UTC surface analysis and satellite imagery through 1440 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A strong cold front is expected to sweep across the Gulf of Mexico Fri. Strong high pressure in its wake will build southward along the Sierra Madre mountains of Mexico leading to a significant tightening of the pressure gradient that will induce a strong gale-force gap wind event in the Gulf of Tehuantepec. Gale-force N winds are forecast to begin late tonight before abruptly increasing to strong gale-force by Fri afternoon, continuing into early on Sat, with possible brief gusts to storm force. Model guidance is trending toward slightly stronger winds up to around storm-force, and if trends continue the gale warning may be upgraded to a storm warning later this afternoon. The timing on the potential storm-force winds would be Fri evening until late Fri night. Seas will build quickly to 18-20 ft Fri night into early Sat. Conditions will improve on Sun with winds diminishing below gale-force on Sun and seas subsiding to below 8 ft by late Mon. Please read the latest High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from Panama near 08N78W to 04N95W. The ITCZ axis extends from 04N95W to 03N106W to 06N120W, then resumes west of a surface trough from 07N127W to 05N140W. Scattered moderate isolated strong convection is evident from 04N to 12N between 115W and 122W. Scattered moderate convection is evident from 04N to 07N between 122W and 131W, and from 05N to 07N between 137W and 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features section for details on an upcoming Gale Warning in the Gulf of Tehuantepec, which may reach near storm-force Fri evening and night. High pressure located southwest of the California Channel Islands extends a ridge southeastward across the offshore waters of Mexico. Moderate to fresh N-NE winds are over the central and southern Gulf of California to near Cabo Corrientes, spilling through Baja California Sur gaps just northwest of Cabo San Lucas. Seas are 2-4 ft in the central and southern California, and 1-2 ft in the northern Gulf of California where winds are moderate or weaker. Winds are moderate or weaker elsewhere, except fresh to strong in the Gulf of Tehuantepec. Seas are 5-8 ft in NW swell west of 110W, except to 9 ft near Clarion Island. Seas of 4-7 ft primarily in NW swell are across the remainder of the waters. For the forecast, outside of the Gulf of Tehuantepec, winds will increase slightly to fresh to strong in the central and southern Gulf of California tonight through Fri morning due to a tightening pressure gradient, then moderate to fresh there through Fri night. A decaying cold front will approach Baja California by the end of the weekend with high pressure building behind it which will spread fresh to strong NW-N winds offshore Baja California from Cabo San Lazaro northward Sun night through Mon evening. Winds will be mainly moderate or weaker elsewhere through the forecast period. Meanwhile, the NW swell will decay through the end of the week. A new set of larger NW swell will arrive offshore Baja California with the fresh to strong winds. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to near gale-force winds are offshore Nicaragua including the Gulf of Papagayo along with seas of 8-9 ft, with fresh winds and 4-7 ft seas offshore the Gulf of Fonseca. Fresh to strong N-NE winds are from the Gulf of Panama south-southwestward, including near the Azuero Peninsula along with 4-7 ft seas. Winds are mainly light to gentle elsewhere, along with 4-6 ft seas primarily in long-period S-SW swell. For the forecast, fresh to strong NE to E winds in the Gulf of Papagayo region will prevail into early next week, near gale- force at times, along with pulsing seas of 7-10 ft. Large fresh swell generated by an upcoming Gulf of Tehuantepec strong gale- force gap wind event is expected to begin to propagate through the Guatemala and El Salvador offshore waters starting Fri night and begin to subside on Sun. Fresh to strong N-NE winds will diminish in the Gulf of Panama later this morning, then pulse to moderate to fresh through the remainder of the forecast period. REMAINDER OF THE AREA... A cold front extends across the northwest waters from 30N134W to 25N140W. Fresh to strong S-SW winds are north of 26N within about 240 nm ahead of the front. Fresh NW winds follow the front. NW swell of 8-11 ft is north of 27N and west of 130W. High pressure southwest of the California Channel Islands extends a ridge southwestward ahead of the cold front to near 20N140W. A pronounced surface trough is south of the ridge along the ITCZ, extending from 12N118W to 03N125W. Fresh to locally strong winds are possible within about 240 nm northwest of the trough. Moderate to fresh trades are elsewhere north of the ITCZ to 11N and west of the trough, with gentle to moderate winds across the remainder of the open waters. Seas of 7-11 ft cover the waters north of the ITCZ to about 22N and west of 112W due to a combination of the winds related to the trough and background NW swell. Seas of 5-7 ft prevail across the remainder of the waters. For the forecast, the trough along the ITCZ will relatively quickly move westward, reaching 140W by Sat night. Associated winds ahead of the trough will be fresh, occasionally and locally strong. Seas of 8-10 ft aided by NW swell will accompany the trough. Meanwhile, fresh to strong winds extending from a Gulf of Tehuantepec gap wind event will extend southwest by Fri evening and reach to 115W by Sat night. The cold front in the northwest waters will weaken and eventually stall by early Sat, while a new cold front pushes southeast of 30N140W by then. The boundaries will merge by Sat afternoon and then push toward Baja California through the weekend. Strong high pressure will build in the wake of the boundaries with fresh to strong trades covering most of the waters west of 120W by Sun night, and moderate to fresh trades elsewhere north of the ITCZ by then. Similar conditions will continue into early next week. NW swell of 8 ft or greater associated with the boundaries will mainly be across the northern waters through Fri night, then push and expand across most of the waters west of 110W, aided by the fresh to strong trades. $$ Lewitsky