Eastern Pacific Tropical Weather Discussion
350 AXPZ20 KNHC 211606 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1605 UTC Mon Sep 21 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 1200 UTC surface analysis and satellite imagery through 1545 UTC. ...SPECIAL FEATURES... Tropical Storm Odalys is centered near 13.9N 129.3W, or about 1230 nm west-southwest of the southern tip of Baja California at 21/1500 UTC, moving northwest at 10 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Peak seas are to near Seas are peaking near 17 ft. Satellite imagery shows that Odalys has become significantly better organized this morning. Numerous strong convection is seen from 09N to 14N between 126W and 135W. Scattered moderate to strong convection is from 05N to 09N between 126W and 133W. 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. Gradual strengthening is expected, 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 Storm Polo is centered near 15.4N 103.4W, or about 220 nm south-southeast of Manzanillo, Mexico at 21/1500 UTC, moving east at 4 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed has increased to 55 kt with gusts to 65 kt. Peak seas are near 23 ft. Satellite imagery indicates that Polo is undergoing significant rapid intensification. Numerous moderate to strong convection is noted within 120 nm of the center, except 180 nm in the NE quadrant. A slow eastward or southeastward motion is expected through tonight. However, a sharp turn toward the west-northwest or northwest is expected by late Tue. On the forecast track, the core of Polo is expected to be near the coast of southwestern Mexico during the next few days. Polo is expected to continue to rapidly intensify, becoming a hurricane by this afternoon and a major hurricane on 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 Thursday. 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 WAVES... The axis of a tropical wave is near 88W north of 01N, moving westward near 10 kt. Scattered moderate to isolated strong convection is from 02N to 12N between 84W and 90W. ...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 16N123W. Numerous moderate to strong convection is within 240 nm north of the trough between 90W-94W. Scattered moderate to isolated strong convection is within 60 nm of the trough between 85W-88W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details on Tropical Storm Polo. Tropical Storm Polo is near 15.4N 103.4W, or about 220 nm south- southeast of Manzanillo, Mexico at 21/1500 UTC, moving east at 4 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed has increased to 55 kt with gusts to 65 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, Tropical Storm Polo will strengthen to a hurricane near 15.3N 102.8W this evening with maximum sustained winds 86 kt gusts 105 kt, move to near 15.1N 102.3W Tue morning, to near 15.4N 102.3W Tue evening, 16.0N 102.8W to near Wed morning, to near 16.8N 103.6W Wed evening, and to near 17.6N 104.8W Thu morning. Polo will change little in intensity as it moves to near 18.6N 107.8W early on Fri 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. ...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 prevail through Thu night across the offshores. Winds and seas will build across in the offshores between Costa Rica and Guatemala early Fri morning as a low pressure develops within the monsoon. ...REMAINDER OF THE AREA... Please see the Special Features section above for details on Tropical Storm Odalys and on Tropical Polo. Tropical Storm Polo is near 15.4N 103.4W, or about 220 nm south- southeast of Manzanillo, Mexico at 21/1500 UTC, moving east at 4 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed has increased to 55 kt with gusts to 65 kt. Tropical Storm Odalys is near 13.9N 129.3W, or about 1230 nm west-southwest of the southern tip of Baja California at 21/1500 UTC, moving northwest at 10 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Outside of Odalys and Polo, fresh to strong winds, and rough seas, are over the waters from 15N to 25N and west of 134W. 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, Tropical Storm Polo will strengthen to a hurricane near 15.3N 102.8W this evening with maximum sustained winds 86 kt gusts 105 kt, move to near 15.1N 102.3W Tue morning, to near 15.4N 102.3W Tue evening, 16.0N 102.8W to near Wed morning, to near 16.8N 103.6W Wed evening, and to near 17.6N 104.8W Thu morning. Polo will change little in intensity as it moves to near 18.6N 107.8W early on Fri. Odalys is forecast to move to near1 4.6N 130.0W this evening, to near 15.2N 129.9W Tue morning, 15.5N 128.9W Tue evening, 15.6N 127.7W Wed morning, then strengthen to a hurricane near 15.8N 126.4W Wed evening with maximums sustained winds 65 kt gusts 80 kt. Odalys is then forecast to reach near 16.4N 124.8W Thu morning, and change little in intensity as it moves to near 17.7N 122.6W early on Fri. Otherwise, high pressure over the area will pretty much maintain gentle to moderate winds. Moderate seas are expected with these winds.