Tropical Weather Discussion

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Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Sun Oct 12 2025 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 2030 UTC. ...TROPICAL WAVES... A tropical wave is along 97W from 07N to 16N drifting west at 5 kt. Convection is described below in the ITCZ/Monsoon trough section. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 13N87W to 1010 mb low pressure near 11N92W, then continues west to 09N125W. The ITCZ extends from 09N125W to beyond 09N140W. Scattered moderate convection is from 11N to 14N between 92W and 98W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... 1005 mb low pressure, the remnants of Raymond, is over the central Gulf of California near 25N110W. Scattered showers and thunderstorms are active over southern Sonora. Moderate to fresh S to SW winds cover much of the southern and central Gulf of California associated with the low pressure, supporting 3 to 5 ft seas. Off the Pacific coast of the Baja Peninsula, moderate to fresh NE winds are active between the general low pressure over the Gulf of California and 1034 mb high pressure centered well to the north near 45N144W. NW swell to 8 ft is impacting the waters off Guadalupe Island and off the northern coast of Baja California Norte. Thunderstorms are active just south of the Gulf of Tehuantepec, associated with a slow moving tropical wave farther south in the deep tropics. For the forecast, the remnant low of Raymond will move north and merge with lower pressure over the southern Colorado River valley. This pattern may support fresh to strong SW winds across the northern Gulf of California late tonight through late Mon. A cold front will move across northern Baja California and the northern Gulf of California late Tue and Wed. Meanwhile, large NW swell impacting Guadalupe Island and off northern Baja California will gradually subside through early Mon. Farther south, conditions may be conducive for low pressure to develop off southern Mexico through mid week. There is a low chance this will become a tropical cyclone, but expect fresh to strong northerly gap winds across the Gulf of Tehuantepec Tue and Wed as the low moves to the south of the area. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate SW winds prevail across most of the region, with seas of 5 to 7 ft in SW swell impacting the offshore waters from Costa Rica northward. Gentle to moderate breezes and 3 to 5 ft seas in SW swell are noted elsewhere farther south. Scattered moderate convection is most robust closest to the monsoon trough offshore Costa Rica. For the forecast, the SW swell will support combined seas to 7 ft off northern Central America through Mon, with generally moderate southwest winds and seas will remain south of the monsoon through the week. A very moist and unstable atmospheric environment will be favorable for showers and thunderstorms to continue to develop over the regional waters. Looking ahead, low pressure may form south of Guatemala by mid- week, and environmental conditions may be conducive for some tropical development of this low as it moves slowly north or northwest late this week, bringing fresh to occasionally strong winds and moderate to rough seas off Guatemala and El Salvador Thu and Fri. ...REMAINDER OF THE AREA... Broad ridging prevails north of the monsoon trough and ITCZ, with moderate to fresh N winds across these waters as high pressure builds southward. Seas are 5 to 7 ft in this region, except for 8 to 9 ft N of 25N between 115W and 130W, where N swell is propagating. Gentle to moderate southerly winds are south of the ITCZ along with seas of 5 to 7 ft. Moderate south to southwest winds and seas of 5 to 7 ft are south of the monsoon trough. For the forecast, the swell north of 25N between 115W and 130W will subside through late Mon. A cold front will move eastward across the waters north of 25N Tue through Thu. A new round of 8 to 10 ft swell will follow the front over the waters north of 25N into mid week. Looking ahead, high pressure building north of the area behind the front will support fresh NE winds north of 10N and west of 130W Thu and Fri. Farther south, weak low pressure may form along the monsoon trough between 115W and 120W through Wed.