Eastern Pacific Tropical Weather Discussion
632 AXPZ20 KNHC 290408 CCA TWDEP Tropical Weather Discussion...Corrected NWS National Hurricane Center Miami FL 0405 UTC Tue Sep 29 2026 Corrected ITCZ/Monsoon Trough section 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 0000 UTC surface analysis and satellite imagery through 0345 UTC. ...SPECIAL FEATURES... Major Hurricane Polo is centered near 25.9N 112.5W, or about 65 nm north of Cabo San Lazaro, Mexico at 29/0300 UTC, moving northeast at 11 kt. Estimated minimum central pressure is 963 mb. Maximum sustained wind speed is 100 kt with gusts to 120 kt. Peak seas are to near 37 ft (11). Satellite imagery reveal that the cyclone is not as well organized as it was earlier, with the eye being clouded up. Numerous moderate to strong convection is seen within 60 nm of the center. Polo is anticipated to acquire a gradual acceleration through Tue. On the forecast track, the core of Polo is expected to make landfall along the coast of Baja California Sur within the next couple of hours, then move inland over southern Sonora Tue morning. Little change in strength is expected before Polo makes landfall on Baja California Sur. Polo is also expected to be a hurricane when it makes its second landfall in mainland Mexico. Rapid weakening is forecast on Tue when Polo moves well inland over mainland Mexico. Polo is expected to produce rainfall totals of 6 to 12 inches across portions of Baja California Sur. Rainfall totals of 4 to 6 inches with maximum totals of 8 expected across southern and central portions of Sonora. This rainfall may produce life- threatening flooding and mudslides, especially in areas of steep terrain. For a complete depiction of forecast rainfall associated with Polo, please see the National Weather Service Storm Total Rainfall Graphic available at hurricanes.gov/graphics_ep2.shtml?rainqpf Swells generated by Polo will affect portions of the coast of the Baja California peninsula and northwestern Mexico during the next day or so. These swells are likely to cause life-threatening surf, rip currents, and coastal flooding. Please consult products from your local weather office. Tropical Storm Rachel is centered near 14.5N 102.9W, or about 220 nm southwest of Acapulco, Mexico at 29/0300 UTC, moving west-northwest at 9 kt. Estimated minimum central pressure is 997 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. Peak seas are to near 20 ft (6 M). Satellite imagery shows that Rachel overall cloud pattern and structure is gradually improving. Numerous strong convection is seen within 180 nm south-southwest of the system center. Numerous moderate to isolated strong convection is elsewhere from 08N to 14N between 102W and 112W. A gradual turn toward the northwest with a slower forward speed is expected during the next few days. On the forecast track, the center of Rachel is predicted to move parallel to, but stay offshore of, the coast of southwestern Mexico. Gradual strengthening is expected during the next few days, and Rachel is forecast to become a hurricane during the next day or so. Rachel is expected to produce rainfall totals of 3 to 6 inches, with isolated maximum totals of 8 inches across coastal portions of the Mexican states of Guerrero, Michoacán and Colima. This rainfall may produce flooding and mudslides, especially in areas of steep terrain. For a complete depiction of forecast rainfall associated with Rachel, please see the National Weather Service Storm Total Rainfall Graphic available at hurricanes.gov/graphics_ep3.shtml?rainqpf Swells generated by Rachel will affect portions of the southwestern coast of Mexico during the next couple of days and spread northward through midweek. These swells are likely to cause life- threatening surf and 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 NHC Forecast/Advisories and Public Advisories at www.hurricanes.gov for more details on Polo and Rachel. Scattered moderate convection remains limited and disorganized in association with an area of low pressure located well east- southeast of the Hawaiian Islands. This activity is seen from from 14N to 18N between 131W and 135W. A 1005 mb low, Invest EP91, is analyzed along the monsoon trough near 14N134W. Although the system has lost some organization today, it is still expected to become a tropical depression during the next day or two while it drifts northeastward. Environmental conditions are expected to become less conducive for development late this week. This system has a high chance of tropical formation within the next 48 hours. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...Corrected The monsoon trough axis extends from northern Colombia across the southwestern Caribbean Sea and to across northern Costa Rica, then to 10N85W to 09N87W and to 11N95W. It resumes west of Rachel at 13N112W, and continues to 16N126W to Invest EP91 near 14N134W 1005 mb and to west of the area at 14N140W. Numerous moderate to isolated strong convection is seen from 07N to 13N between 112W-120W. Scattered moderate convection is south of 10N west of 137W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for information on Major Hurricane Polo and on Tropical Storm Rachel. These systems will impact a large majority of the forecast waters. Elsewhere, fresh northwest to north winds are offshore the Baja California Peninsula and light to gentle winds elsewhere over the Mexican offshore waters and Gulf of California. Rough seas are offshore Baja California, with moderate seas elsewhere, except slight in the northern Gulf of California. For the forecast, Major Hurricane Polo will move to near 27.7N 110.9W Tue morning, then move inland and weaken to a tropical depression near 31.0N 107.7W Tue evening, and dissipate Wed morning. Tropical Storm Rachel is near1 4.5N 102.9W, or about 220 nm southwest of Acapulco, Mexico at 8 PM PDT, and is moving west-northwest at 9 kt. Maximum sustained winds are 50 kt with gusts to 60 kt, and the minimum central pressure is 997 mb. Rachel will move to near 15.2N 104.3W Tue morning, then strengthen to a hurricane near 16.5N 105.8W Tue evening with maximum sustained winds 65 kt gusts 80 kt, then continue to gradually strengthen as it moves to near 17.9N 107.0W Wed morning, to near 18.9N 107.8W Wed evening with maximum sustained winds 80 kt gusts 100 kt, to near 19.5N 108.5W Thu morning with maximum sustained 85 kt gusts 105 kt and to near 19.9N 109.1W Thu evening. Rachel is forecast to move to be east-northeast of the Revillagigedo Islands by Fri evening. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate east to southeast winds are over the western portion of the Guatemala offshore waters. Otherwise, a rather light gradient is maintaining mostly gentle winds across these waters. Moderate seas prevail, except slight seas are present in and near the Gulf of Panama. For the forecast, a rather light pressure gradient will maintain moderate or weaker winds over the offshore waters along with mostly moderate seas through the period. ...REMAINDER OF THE AREA... Please see the Special Features section above for information on Hurricane Polo, on Tropical Storm Rachel, and on a broad area low pressure in the far western waters that has potential for tropical cyclone formation this week. Away from the tropical cyclones, fresh northeast winds are over the western portion of the area, primarily west of a from about 30N120W to 19N132W to 15N140W. Seas are 8 to 11 ft in mixed swell over these waters. Mostly gentle to moderate winds are elsewhere. The remnant low of Odalys is near 22N123W with a pressure of 1004 mb. Fresh to strong north to northeast winds are within 180 nm of the low in the NW quadrant along with seas of 8 to 11 ft. The low is forecast to move southward through Tue, then weaken to a trough Wed. Winds will subside, but rough seas will prevail due to the influences of the nearby tropical systems. For the forecast, Tropical Storm Rachel is near 14.5N 102.9W, or about 220 nm southwest of Acapulco, Mexico at 8 PM PDT, and is moving west-northwest at 9 kt. Maximum sustained winds are 50 kt with gusts to 60 kt, and the minimum central pressure is 997 mb. Rachel will move to near 15.2N 104.3W Tue morning, then strengthen to a hurricane near 16.5N 105.8W Tue evening with maximum sustained winds 65 kt gusts 80 kt, then continue to gradually strengthen as it moves to near 17.9N 107.0W Wed morning, to near 18.9N 107.8W Wed evening with maximum sustained winds 80 kt gusts 100 kt, to near 19.5N 108.5W Thu morning with maximum sustained 85 kt gusts 105 kt and to near 19.9N 109.1W Thu evening. Rachel is forecast to move to be east- northeast of the Revillagigedo Islands by Fri evening. Scattered moderate convection remains limited and disorganized in association with an area of low pressure located well east- southeast of the Hawaiian Islands. This activity is seen from from 14N to 18N between 131W and 135W. A 1005 mb low, Invest EP91, is analyzed along the monsoon trough near 14N134W. Although the system has lost some organization today, it is still expected to become a tropical depression during the next day or two while it drifts northeastward. Environmental conditions are expected to become less conducive for development late this week. This system has a high chance of tropical formation within the next 48 hours. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details.