000 AXPZ20 KNHC 092203 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Thu Feb 09 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 1800 UTC surface analysis and satellite imagery through 2145 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A strong cold front will enter the Gulf of Mexico Fri and move quickly across the W half of the Gulf. Strong high pressure behind this front will build southward across eastern Mexico and induce gale-force northerly gap winds across the Gulf of Tehuantepec Fri evening. These will quickly become strong gale-force winds Fri night through Sat. This will produce another broad reaching area of gap winds that will extend well beyond the Gulf of Tehuantepec over the weekend, with strong winds reaching to near 10N100W by Sat afternoon. Storm force winds are briefly possible early Sat night. Seas are likely to peak around 20 ft from late Sat afternoon through late Sat night. Gale conditions are expected to continue across Tehuantepec through late Sun before diminishing. Pacific Significant Seas: The earlier observed seas of 10-12 ft over the waters from 10N to 22N and W of 134W have subsided to just below 12 ft, however, large NW swell that was generated a few days ago by an intense storm system well N of the area is entering the NW part of the area behind the cold front associated to that low pressure system. The swell is forecast to gradually outrun the front as it weakens through tonight. Seas of 12 ft and greater will reach 30N140W by early this evening and spread southeastward to near 130W through Fri afternoon. NW swell at 14-15 seconds is expected to dominate. Strong high pressure behind the front will increase the pressure gradient across the regional waters from NW to SE into the weekend, and create a large area of fresh to strong N to NE winds to the west of 125W by Sat afternoon. Peak seas around 15 ft will reach the NW waters early Fri. Please read the latest High Seas Forecast at https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more information. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from northwestern Colombia near 10N75W and continues southwestward to 05N86W to 04N92W and to 04N104W, where the latest scatterometer data indicates that it transitions to the ITCZ and continues to 02N115W and northwestward to 07N128W and to 07N140W. Scattered moderate convection is within 120 nm N of the ITCZ between 126W-132W and within 60 nm N of the ITCZ between 123W-129W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Strong high pressure persists north of the Pacific waters W of 120W. Its associated ridge across the Baja California offshore waters has weakened since yesterday. Fresh to strong NNW winds continue across the Gulf of California, where seas are 4-6 ft across central and southern sections, and to 7 ft near the coast at Cabo San Lucas. Moderate N to NE winds prevail across the Baja California offshore waters to Cabo Corrientes, and become NE well offshore of Baja Sur. Seas over these waters have subsided to 5-7 ft in decaying long-period NW swell. Gentle to moderate winds are elsewhere offshore of southwestern Mexico. Seas are 4-6 ft elsewhere offshore Mexico. For the forecast, high pressure NW of the area will shift northeastward through early Fri. This will allow for fresh to strong NNW winds in the Gulf of California to slowly diminish through late Fri night. Moderate to locally fresh N to NE winds across the Baja waters will diminish slightly through Fri morning, except for narrow zones of fresh NE gap winds that will spill from the Gulf of California across Baja and into the Pacific waters. Seas will slowly subside area wide during this time. Fresh to strong northerly gap winds in the Gulf of Tehuantepec will increase to gale-force starting Fri evening. Fresh to strong NW winds will move into the far northern offshore waters of Baja California from late Fri night into Sun, as a cold front moves through the area and dissipates, accompanied by building seas in NW swell. Fresh to strong S to SW winds develop in the far northern Gulf of California on Tue ahead of a strong cold front. These winds are expected to become strong to near gale SW to W winds Tue night along with building seas to around 9 ft. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Strong NE winds are offshore Nicaragua and the Gulf of Papagayo region, extending offshore to near 90W. Seas are 6-8 ft in this area. Fresh N to NE winds are in the Gulf of Panama, extending southward to 05N, where seas are 4-7 ft. Light to gentle variable winds prevail 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 and Nicaragua waters will persist through early next week. Winds may reach near gale-force at night from Fri through Sun. Moderate to fresh N-NE winds in the Gulf of Panama will change little into next week, except pulse to strong Sun night. A significant gale-force gap wind event in the Gulf of Tehuantepec region is expected over the weekend. Large NW swell generated from this event will propagated through the Guatemala and El Salvador offshore waters Sat through late Sun night. REMAINDER OF THE AREA... Broad high pressure is over the area. It is causing a cold front over the NW corner of the area to weaken as is bridges across it. This pressure pattern earlier, at the time the front wasn't weakening, helped to diminish some of the coverage area of fresh NE to E winds across the waters from 08N to 24N and W of about 130W. Large NE wind generated seas are combining with NW swell moving through these waters resulting in gradually subsiding seas of 8-12 ft. Please see the Special Features section for information concerning these significant seas. Seas are 5-7 ft E of 110W due to mixed long-period NW swell mixing with S swell. Elsewhere, moderate wind and seas are noted. An area of broken to overcast low and mid-level clouds, with isolated showers and thunderstorms is observed N of the ITCZ from 10N to 15N and between 128W-136W. This area of cloudiness and shower/thunderstorm activity is being aided by a broad mid- level trough that is present to its NW. For the forecast, an extensive and strong area of high pressure that will build east-southeastward in the wake of the weakening cold front will act to produce fresh to strong NE to E winds to the west of 130W tonight through Fri. Seas will build again to 12 ft and greater over the western part of the area on Fri as the large NW swell begins to propagate into that part of the area. The weakening front will approach the Baja offshore waters Sat, with the strong high pressure behind it tightening the gradient resulting in fresh to strong N to NE winds and large seas over much of the area waters W of 120W through the weekend. $$ Aguirre