Pacific Discussion

  • NHC East Pacific Tropical Weather Discussion
    by (nhcwebmaster) on September 28, 2022 at 10:04 PM

    000 AXPZ20 KNHC 282203 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Wed Sep 28 2022 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 2150 UTC. ...SPECIAL FEATURES... South of the Southern Coast of Mexico: Showers and thunderstorms associated with a 1007 mb low pressure south of the southern coast of Mexico near 14N102W continue to show signs of organization. Numerous moderate isolated strong convection is from 12N to 16N between 101W and 106W. Scattered moderate convection is elsewhere from 07N to 17N between 100W and 111W. Recent scatterometer data show fresh to locally strong winds within 120 nm from the center of the low. Peak seas in the east semicircle are 8 to 9 ft. Environmental conditions appear conducive for development, and a tropical depression is likely to form during the next couple of days while the system moves westward to west-northwestward off the coast of southern and southwestern Mexico. This system has a high chance of tropical cyclone formation through the next 48 hours, and the next 5 days. Western East Pacific: A 1008 mb low, remnants of Newton is located nearly 1,100 nautical miles southwest of the southern tip of the Baja California peninsula. Scattered moderate convection is within 210 nm N semicircle of the low center with recent scatterometer data showing fresh to locally strong winds in this same region. An additional slight development of this system is possible during the next day or two and could briefly become a tropical depression again while it moves generally westward over the western portion of the eastern North Pacific. Environmental conditions are expected to become less conducive for additional development by the end of the week. This system has a medium chance of tropical cyclone formation through the next 48 hours and 5 days. Please read the latest NHC Tropical Weather Outlook at for more details on both systems. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 09N84W to 1007 mb low pressure near 14N102W to 1008 mb low pressure near 13N124W to 08N134W. The ITCZ axis extends from 08N134W to 08N140W. Aside from the convection associated with the areas of low pressure in the Special Features section, scattered moderate convection is noted N of 02N E of 84W, from 10N to 15N between 92W and 98W, and from 06N to 13N between 111W and 122W. Similar convection is in the Costa Rica and Nicaragua offshore waters. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please read the Special Features above for details on an area of low pressure near 14N102W. Fresh to locally strong N-NE winds prevail in the Gulf of Tehuantepec region with seas to 8 ft. Gentle to moderate NW winds are offshore Baja California Norte, with light to gentle variable winds offshore Baja California Sur. Light to gentle SE winds are noted in the Gulf of California where seas are to 3 ft. In the SW Mexican offshore waters, moderate to fresh winds are across the region between Guerrero and Colima along with seas to 9 ft associated with the low near 14N102W. For the forecast, other than the area of low pressure, fresh N to NE winds across the Gulf of Tehuantepec will to pulse to strong at night through the weekend. Winds may reach near gale force there Thu and Fri nights. Moderate to locally fresh NW to N winds will continue to dominate the Baja California Norte offshore waters through the weekend. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The monsoon trough extends just offshore the coasts of Guatemala east-southeast to near the Papagayo region to the SW Caribbean. Moderate S-SW winds dominate the offshore waters S of 05N, except for gentle to locally moderate W to NW winds just north of the monsoon trough. Seas are 5-6 ft in S-SW swell across the region. Scattered showers and isolated thunderstorms extend offshore from Colombia NW to Nicaragua. For the forecast, moderate to locally fresh southerly winds will prevail offshore southern Colombia and Ecuador to the Galapagos Islands, with gentle to moderate winds elsewhere, becoming NE-E from the Papagayo region northward this weekend. Seas of 6-8 ft will dominate the waters through Thu before subsiding slightly Fri. Seas will build offshore Guatemala by the end of the week due to an extended gap wind event currently developing across the Tehuantepec region. REMAINDER OF THE AREA... Please read the Special Features above for details on the remnants of Newton near 13N124W, and on an area of low pressure near 14N102W. High pressure of 1021 mb is located near 28N136W. Light to gentle anticyclonic winds and 4-6 ft seas in mixed swell are under the high north of 25N and west of 127W. Moderate to fresh southerly winds and seas of 7-9 ft are south of the monsoon trough from 04N to 11N between 100W and 120W. Gentle to moderate winds and 5-7 ft seas prevail elsewhere. For the forecast, other than the remnants of Newton and the low pressure near 14N102W, weak high pressure will dominate the northern waters through the week, while a slow moving cold front attempts to move into the NW waters late tonight before lifting back northwest or dissipating. The moderate to fresh southerly winds and 7-9 ft seas south of the monsoon trough will diminish and subside towards the end of the week, then increase again Sat as mixed SE and SW swell moving into the region. $$ Ramos