Pacific Discussion

  • NHC East Pacific Tropical Weather Discussion
    by nhcwebmaster@noaa.gov (nhcwebmaster) on March 28, 2024 at 3:56 PM

    241 AXPZ20 KNHC 281556 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Thu Mar 28 2024 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 1500 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: Gale force winds and seas of 9 to 13 ft are currently occurring at the Gulf of Tehunatepec. These marine conditions are forecast to persist tonight and Fri morning, with seas building to 10 to 14 ft by tonight. Swell generated by this gap wind event will spread southwestward, creating 8 to 11 ft seas as far west as 100W and as far south as 09N on Fri morning. Both winds and seas should begin to diminish late Fri afternoon. Marine interests in the Tehuantepec area, especially local fishermen need to take necessary action to avoid these hazardous marine conditions. Please read the latest High Seas Forecast issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for more detail. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... An equatorial trough extends from a 1013 mb low pressure over northern Colombia to 07N100W to the Equator at 120W. The ITCZ is south of the Equator and runs westward from 01S110W to 03S125W. Scattered moderate convection is noted from 02N to 07N between 88W and 120W. Scattered moderate to isolated strong convection is from 02N to 06N W of 130W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A Gale Warning is in effect for the Gulf of Tehuantepec. Please, read the Special Features section for more details. A broad surface ridge continues to dominate the offshore forecast waters of Baja California with gentle to moderate northerly winds and seas of 5 to 7 ft. For the Gulf of California, moderate to fresh NW winds and 3 to 5 ft seas are present across central and southern gulf, while light to gentle winds and seas of 1 to 3 ft exist at the northern gulf. Other than the Gale Warning area in the Tehuantepec region, light to gentle winds and seas at 4 to 6 ft in mixed moderate swells prevail for the southern Mexico offshore waters. For the forecast, gale conditions and rough to very rough seas will persist in the Tehuantepec region through Fri morning. A strong cold front is forecast to enter the offshore waters of Baja California and northern Gulf of California on Sat, bringing with it increasing winds and large NW swell. This swell could generate high seas at the outer offshore waters north of Punta Eugenia by Sun morning. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR Moist, convergent SW to W winds are triggering widely scattered showers and a few thunderstorms south of the Galapagos Islands, and off central Costa Rica. Refer to the Monsoon Trough/ITCZ section for additional weather in the region. Otherwise, gentle with locally moderate S to SW winds and 3 to 6 ft seas prevail across the offshore waters of Ecuador, Colombia, Panama, Costa Rica and the Galapagos Islands. Light to gentle winds and seas at 2 to 4 ft are found offshore of Guatemala, El Salvador and Nicaragua. For the forecast, convergent southwesterly winds along with abundant moisture will continue to support sporadic showers and thunderstorms near the Galapagos Islands and in the Costa Rica and Panama offshore waters through at least Fri. Winds and seas could be higher near thunderstorms. Otherwise, light to gentle winds and slight to moderate seas will prevail across the entire region through Thu night. Starting Fri, increasing gap winds and rising seas will occur in the Papagayo area, and Gulf of Panama as high pressure builds north of the area. Also on Fri, swell generated by gap winds at the Tehuantepec region will cause rough seas across the far southwestern offshore waters of Guatemala and El Salvador. ...REMAINDER OF THE AREA... A ridge dominates the northern forecast waters while a weakening cold front extends from 30N130W to 27N140W generating some shower activity. The pressure gradient between this ridge and lower pressures near the equatorial trough/ITCZ maintains moderate to fresh trades along with 7 to 9 ft seas from 07N to 20N west of 125W, confirmed by the most recent scatterometer data. Gentle to moderate anticyclonic flow along with 5 to 7 ft seas are evident across most of the waters north of 20N and W of 120W. Gentle with locally moderate NE winds and seas of 5 to 7 ft exist north of the equatorial trough between 100W and 120W. Mostly gentle ENE to SE winds and 4 to 7 ft seas in mixed moderate swells prevail for the remainder of the Pacific waters. For the forecast, the surface ridge will linger across the waters west of Baja California as the weakening front moves southeastward across waters north of 20N. This will allow trade winds from 07N to 20N west of 125W to diminish. Residual NW swell will still big enough to keep 7 to 9 ft seas in this area until this evening. A strong cold front will enter the Pacific waters west of Baja California Norte on Fri, followed by fresh to strong northerly winds and large seas. $$ GR