000 AXPZ20 KNHC 031003 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Fri Feb 3 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 0920 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Storm Warning: A strong cold front will move across the Gulf of Mexico tonight through 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 across southern Mexico. Strong N winds in the Gulf of Tehuantepec have recently increased to gale force north of 15N, and will rapidly increase and expand during the day Fri, and briefly reach storm-force Fri evening into the early overnight hours. Winds will diminish back to strong gale-force by early Sat, then gradually diminish below gale-force early Sun. Very large seas will build with these gale to storm-force winds, peaking at 18-22 ft Fri evening into Sat morning. 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 near 10N75W to 05.5N90W. The ITCZ extends from 05.5N90W to 02N105W to 05.5N115W to beyond 06N140W. Scattered moderate convection is noted from 05.5N to 09N between 120W and 138W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features section for details on an upcoming Storm Warning in the Gulf of Tehuantepec. Gale force northerly winds currently prevail across the immediate Gulf waters north of 15N, where seas are 9 ft and building. Gale force winds are expected to end early Sun, then remain strong through Mon. High pressure located southwest of the California Channel Islands extends a ridge southeastward across the offshore waters of Mexico to 105W. Fresh to locally strong N-NW winds are over the Gulf of California south of 29N to near Cabo Corrientes, spilling through Baja California Sur gaps just northwest of Cabo San Lucas. Seas are 3-6 ft in the Gulf of California south of 28N and 2-3 ft in the northern Gulf of California where winds are moderate or weaker. N to NE winds are moderate or weaker elsewhere across the Baja California offshore waters. Seas are 5-8 ft in NW swell west of 110W, and 4-7 ft 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 early Fri afternoon due to a tightening pressure gradient, then moderate to fresh there through early Sat. A decaying cold front will approach Baja California by late Sun, with high pressure building across the Baja waters with and behind it. This will produce fresh to strong NW-N winds offshore Baja California from Cabo San Lazaro northward Sun night through Mon night. Similar winds will spread south through the Gulf of California. New NW swell will arrive across the offshore Baja waters ahead of the front, and with the fresh to strong winds. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong NE winds are offshore of Nicaragua, including the Gulf of Papagayo area, to near 90W, and extend northward to near the Gulf of Fonseca. Seas of 6-8 ft prevail across these waters. Fresh N-NE winds are from the Gulf of Panama south- southwestward, including near the Azuero Peninsula, producing seas of 4-7 ft seas. Winds are mainly light to gentle elsewhere, along with 4-6 ft seas primarily in SW swell. For the forecast, fresh to strong NE to E winds across the Gulf of Papagayo region will prevail into early next week, near gale- force at times, producing periods of 7-10 ft seas. Large fresh swell generated by an upcoming Gulf of Tehuantepec storm-force gap wind event is expected to begin to propagate through the Guatemala and El Salvador offshore waters Fri evening through Sun. Fresh to strong N-NE winds will pulse in the Gulf of Panama, mainly at night, through Sat night. REMAINDER OF THE AREA... A cold front has begun to slow its forward progress across the northwest waters, and now extends from 30N129W to 23N140W. Fresh to strong S-SW winds are north of 29N within about 150-210 nm ahead of the front. Moderate to fresh NW winds follow the front. NW swell producing seas of 8-11 ft is north of 26N and west of 127W. High pressure southwest of the California Channel Islands extends a ridge southwestward ahead of the cold front to near 22N135W. A low level trough is south of the ridge along the ITCZ, south of 13N along 125W. Fresh to locally strong winds are occurring within about 240 nm northeast of the trough. Moderate to locally fresh trades are elsewhere north of the ITCZ to 18N 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 21N and west of 110W due to a combination of the winds related to the trough and background NW swell. Seas of 5-7 ft in mixed SW and NW swell prevail across the remainder of the waters. For the forecast, the trough along the ITCZ will relatively quickly move westward, reaching 140W 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 well southwest by Fri evening and reach to 110W by Sat. 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. $$ Stripling