Eastern Pacific Tropical Weather Discussion
355 AXPZ20 KNHC 220021 CCA TWDEP Tropical Weather Discussion...Corrected NWS National Hurricane Center Miami FL 2205 UTC Mon Sep 21 2026 Corrected Remainder of the Area 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 1800 UTC surface analysis and satellite imagery through 2145 UTC. ...SPECIAL FEATURES... Recently upgraded Hurricane Polo is centered near 15.1N 102.7W, or about 250 nm south-southeast of Manzanillo, Mexico at 21/2100 UTC, moving east-southeast at 5 kt. Estimated minimum central pressure is 974 mb. Maximum sustained wind speed is 75 kt with gusts to 90 kt. Peak seas have spiked up to near 27 ft. Satellite imagery shows that Polo has a ragged eye on both visible and infrared images, with very deep convection starting to wrap around a broken eyewall. Numerous strong convection is within 90 nm of the center in the E semicircle. Numerous moderate to strong convection is within 180 nm of the center in the W quadrant. Scattered moderate to isolated strong convection is elsewhere from 12N to 17N between 99W and 107W. Polo is forecast to maintain its current motion tonight, with a sharp turn toward the northwest and west- northwest anticipated late Tue into Wed. On the forecast track, the core is Polo is expected to be near or south of the coast of southwestern Mexico during the next few days. Polo is expected to continue rapidly intensifying, becoming a major hurricane by Tue, with further intensification likely though midweek. Polo is expected to produce rainfall totals of 4 to 8 inches, with isolated maximum totals up to 12 inches across coastal portions of the Mexican states of Guerrero and Michoacán through Thursday. This rainfall may produce life-threatening flooding and mudslides, especially in areas of steep terrain. Rainfall of 3 to 6 inches is possible in coastal portions of Oaxaca, Colima, and Jalisco through Thu. Swells generated by Polo are expected to begin affecting portions of the coast of southwestern Mexico on Tue. 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 Polo NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. Tropical Storm Odalys is centered near 14.0N 130.0W, or about 1260 nm west-southwest of the southern tip of Baja California at 21/2100 UTC, moving northwest at 7 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Peak seas are near 19 ft. Satellite imagery shows that the deep convection, with very cold cloud tops has diminished since this morning and the cloud temperatures have warmed. Numerous moderate to strong convection is seen from 08N to 16N between 124W and 137W. Scattered moderate to isolated strong convection is south of 08N and west 130W. An eastward turn is forecast on Tue, followed by a gradual turn toward the east-northeast by midweek, and toward the northeast by the end of the week. Some strengthening is expected during the next 48 hours, and Odalys is forecast to become a hurricane by mid-week. 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 Odalys NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... The axis of a tropical wave is near 88W north of 01N, moving westward at about 5 to 10 kt. Scattered moderate to isolated strong convection is from 02N to 11N between 83W and 86W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis from northwest Colombia westward to across southern Nicaragua and to 11N86W to 09N89W and to 12N97W. It resumes to the southwest of Polo at 13N108W, to 12N115W and to near 16N123W. Numerous moderate to strong convection is from 04N to 12N between 90W-94W. Scattered moderate convection is within 60 nm south of the trough between 117W-119W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details on recently upgraded Hurricane Polo. Recently upgraded Hurricane Polo is near 15.1N 102.7W, or about 250 nm south-southeast of Manzanillo, Mexico at 21/2100 UTC, moving east-southeast at 5 kt. Estimated minimum central pressure is 974 mb. Maximum sustained wind speed has increased to 75 kt with gusts to 90 kt. Aside from conditions associated with Tropical Storm Polo, moderate winds and moderate seas are west of the Baja California peninsula. Gentle to moderate winds and slight seas are over the Gulf of California. Moderate or weaker winds and moderate seas are elsewhere. For the forecast, Hurricane Polo will continue to strengthen as it moves to near 14.9N 102.3W late tonight with maximum sustained winds 100 kt gusts 120 kt, to near 14.9N 102.0W Tue afternoon with maximum sustained winds 125 kt gusts 150 kt, to near 15.4N 102.2W late Tue night with maximum sustained winds 140 kt gusts 170 kt, to near 16.1N 102.9W Wed afternoon with maximum sustained winds 145 kt gusts 175 kt, then begin to slowly weaken as it reaches to near 17.0N 104.0W late Wed night and move to near 17.7N 105.5W Thu afternoon. Polo will move to near 18.6N 108.6W Fri afternoon. Otherwise, moderate to locally fresh NW winds will prevail across the offshore Baja California waters through early Fri morning when conditions in Baja California Sur offshores will start to deteriorate due to the proximity of Polo. Looking ahead, Tropical Storm Odalys currently well to the southwest of the southern tip of Baja California is forecast to strengthen to a hurricane and reach near 20N121W on Sat. Also, an area of low pressure could form in a few days to the south of the Gulf of Tehuantepec. Thereafter, environmental conditions appear favorable for gradual development, and a tropical depression could form late this week or this weekend while the system moves slowly west-northwestward to northwestward, parallel to the coast of southern and southwestern Mexico. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate or weaker winds and moderate seas prevail across the region. For the forecast, gentle to moderate winds and moderate seas will continue over the offshore waters through the period, except winds are expected to become moderate fresh over the offshore waters between northern Costa Rica and Guatemala beginning Thu night as a low pressure area possibly forms to the south of the Gulf of Tehuantepec along the monsoon trough. ...REMAINDER OF THE AREA... Please see the Special Features section above for details on recently upgraded Hurricane Polo and on Tropical Storm Odalys. Recently upgraded Hurricane Polo is near 15.1N 102.7W, or about 250 nm south-southeast of Manzanillo, Mexico at 21/2100 UTC, moving east-southeast at 5 kt. Estimated minimum central pressure is 974 mb. Maximum sustained wind speed has increased to 75 kt with gusts to 90 kt. Tropical Storm Odalys is near 14.0N 130.0W, or about 1260 nm west-southwest of the southern tip of Baja California at 21/2100 UTC, moving northwest at 7 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Outside of Odalys and Polo, fresh to strong winds, and rough seas, are over the waters from 15N to 25N and west of 136W due to a tight gradient between high pressure over the northwest portion of the area, Odalys and a remnant low pressure west of 140W. Gentle to moderate winds, and moderate seas, prevail elsewhere north of the monsoon trough. Moderate or weaker winds and moderate seas remain south of the monsoon trough For the forecast, Hurricane Polo will continue to strengthen as it moves to near 14.9N 102.3W late tonight with maximum sustained winds 100 kt gusts 120 kt, to near 14.9N 102.0W Tue afternoon with maximum sustained winds 125 kt gusts 150 kt, to near 15.4N 102.2W late Tue night with maximum sustained winds 140 kt gusts 170 kt, to near 16.1N 102.9W Wed afternoon with maximum sustained winds 145 kt gusts 175 kt, then begin to slowly weaken as it reaches to near 17.0N 104.0W late Wed night and move to near 17.7N 105.5W Thu afternoon. Polo will move to near 18.6N 108.6W Fri afternoon. Tropical Storm Odalys is forecast to gradually intensify as it moves to near 14.5N 130.0W late tonight, to near 15.0N 129.5W Tue afternoon with maximum sustained winds 55 kt gusts 65 kt, to near 15.2N 128.5W late Tue night, then strengthen to a hurricane near 15.3N 127.2W Wed afternoon with maximum sustained winds 70 kt gusts 85 kt, and move to near 16.4N 124.4W Thu afternoon. Odalys will begin to slowly weaken as it reaches to near 17.9N 122.4W Fri afternoon. Otherwise, high pressure over the area will pretty much maintain gentle to moderate winds. Moderate seas are expected with these winds.