Tropical Weather Discussion

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Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Oct 13 2026 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 0900 UTC. ...SPECIAL FEATURES... Hurricane Simon is centered near 20.6N 107.2W at 13/0900 UTC, moving northwest at 3 kt. Estimated minimum central pressure is 977 mb. Maximum sustained wind speed is 80 kt with gusts to 100 kt. Peak seas are near 20 ft. Numerous moderate to strong convection is within 45 nm of the center. Scattered to numerous moderate and isolated strong convection is elsewhere from 17N to 22N between 105W and 110W. Simon is forecast to continue on a slow northward track the next few days. Simon could approach the coast of western Mexico later this week. Simon is expected to produce rainfall totals of 5 to 10 inches across coastal west- central Mexico with isolated maximum amounts of 15 inches over the state of Sinaloa by Thursday. This rainfall will produce life- threatening flooding and mudslides or worsen any on- going flooding, especially in areas of steep terrain. Swells generated by Simon will affect portions of the coast of southwestern and west- central Mexico during the next few days, as well as the southern Gulf of California. These swells are likely to cause large and powerful surf and life- threatening rip current conditions. Please consult products from your local weather office. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest Simon NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. South of Southern Mexico (EP93): A broad area of low pressure located several hundred miles south- southwest of the coast of Guatemala continues to show improved signs of organization with increased shower and thunderstorm activity. The environmental conditions are forecast to be conducive for further development of the system, and a tropical depression or tropical storm is expected to form well south of southern Mexico within the next day or so. The system is expected to move generally west-northwestward around 10 mph. There is a high chance for tropical cyclone development through next 48 hours. In anticipation of this system developing, a gale warning has been issued. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 08N83W to 09N95W to 05N107W. The ITCZ extends from 05N107W to 04N120W to 07N140W. Scattered moderate and isolated strong convection is noted from 00N to 08N E of 99W, from 04N to 14N between 91W to 100W, and from 02N to 06N between 100W and 130W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for information on Hurricane Simon, and for a gale warning associated with EP93. Aside from conditions associated with Simon, fresh to locally strong winds are funneling through the Gulf of Tehuantepec in response to a deepening low pressure (EP93) south of the area. Elsewhere, a stationary front extends from the northern Gulf of California across Baja California Norte to near 21N129W. Fresh SW winds are in the northern Gulf ahead of the front. Gentle to moderate winds, and slight to moderate seas, prevail elsewhere over the Gulf. Moderate to fresh winds and rough seas are north of the front. Gentle to moderate winds, and moderate to rough seas dominate the remainder of the discussion waters. For the forecast, Hurricane Simon is near 20.6N 107.2W at 2 AM PDT, and is moving northwest at 3 kt. Maximum sustained winds are 80 kt with gusts to 100 kt, and the minimum central pressure is 977 mb. Simon will move to 20.7N 107.4W this afternoon, 20.9N 107.7W Wed morning, 21.0N 107.8W Wed afternoon, 21.2N 107.9W Thu morning, 21.8N 108.0W Thu afternoon, and 23.0N 108.1W Fri morning. Simon will weaken to a tropical storm near 24.2N 108.1W early Sat. A stationary front moving across the northern waters will gradually dissipate today. Rough seas in NW swell west of Baja California will gradually diminish through early Wed. Elsewhere, a broad area of low pressure located several hundred miles south- southwest of the coast of Guatemala continues to show improved signs of organization with increased shower and thunderstorm activity. The environmental conditions are forecast to be conducive for further development of the system, and a tropical depression or tropical storm is expected to form well south of southern Mexico within the next day or so. The system is expected to move generally west-northwestward around 10 mph. There is a high chance for tropical cyclone development through next 48 hours. In anticipation of tropical cyclone development, a gale warning has been issued for portions of the waters south of southern Mexico. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong winds, and rough seas, associated with EP93 cover the waters well offshore Guatemala and El Salvador. Gentle to moderate winds, and moderate to locally rough seas, prevail over the remainder of the offshore waters. For the forecast, fresh to strong winds and rough seas, associated with EP93, well offshore Guatemala and El Salvador will decrease through midweek as EP93 moves further from the area. Otherwise, a weak pressure gradient will support moderate or lighter winds, and moderate seas dominated by SW swell across much of the forecast waters through the end of the week. Numerous showers and thunderstorms are expected to remain active across the waters E of 85W today. ...REMAINDER OF THE AREA... A stationary front extends across the NE waters from Baja California Norte to 21N129W. Moderate to fresh winds and rough seas of 7 to 10 ft in NW swell cover the waters N of 20N. Light to gentle winds and seas of 6 to 8 ft in merging NW and SW swell generally prevail elsewhere S of 20N W of 120W, except for moderate SE to S winds near the equator. For the forecast, the stationary front will gradually dissipate through Tue. Large SW swell will affect the waters S of the Equator and west of 105W over the next couple of days, followed by another pulse of large S-SW swell arriving into the waters W of 100W Wed night.