Eastern Pacific Tropical Weather Discussion
077 AXPZ20 KNHC 220840 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Sep 22 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 surface analysis and satellite imagery through 0730 UTC. ...SPECIAL FEATURES... Major Hurricane Polo is centered near 14.6N 101.8W at 22/0900 UTC, moving east-southeast at 5 kt. Estimated minimum central pressure is 935 mb. Maximum sustained wind speed is 130 kt with gusts to 160 kt. Peak seas have risen up to near 36 ft or 11.0 m, and may be even higher. Satellite imagery shows that Polo has a clearly and well defined eye on infrared images, with incredibly deep convection wrapping around an eyewall. Numerous strong convection is present within 120 nm of the center. Scattered moderate isolated strong convection is present elsewhere from 10N to 17N between 97W and 106W. Polo is moving toward the east- southeast. This general motion is expected to continue today, with a sharp turn toward the northwest and west-northwest anticipated tonight and Wed. On the forecast track, the core of Polo is expected to be near the coast of southwestern Mexico during the next few days, although forecast to remain offshore. Polo is a category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale. Continued rapid intensification is forecast, and Polo could become a Category 5 hurricane later today. Heavy rainfall associated with Polo will impact coastal portions of southwest Mexico through Thu. This rainfall may produce life- threatening flooding and mudslides, especially in areas of steep terrain. Swells generated by Polo are expected to affect portions of the coast of southwestern Mexico during the next few days. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. Tropical Storm Odalys is centered near 14.7N 130.4W at 22/0900 UTC, moving north-northwest at 6 kt. Estimated minimum central pressure is 998 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Peak seas are near 20 ft or 6.0 m. Satellite imagery shows deep convection with numerous moderate to strong convection seen within 75 nm in the NE quadrant, 210 nm in the S semicircle, and 90 nm in the NW quadrant. Scattered moderate isolated strong convection is found elsewhere within 410 nm in the SE semicircle and 120 nm in the NW semicircle. Odalys is moving toward the north-northwest. A turn toward the northeast and then east-northeast is expected over the next day or so. An east-northeast to eastward motion is expected through the end of the week. Additional strengthening is forecast, and Odalys could become a hurricane later today or tonight. 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 on both systems. Heavy Rainfall over Central America: A mid to upper-level trough currently extends over the NW Caribbean while relatively warm sea surface temperatures are present, and in addition there is a potential for a Central American Gyre to form during the next several days. All of these factors are expected to lead to enhanced moisture funneling into Central America and the Caribbean to support heavy rainfall from September 22nd through the 25th. There is still some uncertainty regarding the exact location of heaviest rainfall, but for now heavy rainfall looks likely. Heavy rainfall in these regions will raise concerns for life-threatening flash flooding and landslides. Please refer to local weather services as well as the International Desk at the Weather Prediction Center for more information. Please consult products from your local weather office. ...TROPICAL WAVES... The axis of a tropical wave is near 90W north of 01N, moving westward at around 10 kt. Nearby convection is described below with the monsoon trough. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from the SW Caribbean Sea northwestward to across portions of Central America, and is not present over the discussion waters east of 140W due to the circulations of Hurricane Polo and Tropical Storm Odalys. Other than the convection associated with those systems and described above, isolated to widely scattered moderate isolated strong convection is noted from 00N to 15N between 77W and 102W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details on rapidly intensifying Major Hurricane Polo. Aside from conditions associated with Polo, moderate to fresh NW winds are offshore Baja California per recent ASCAT scatterometer data, with moderate or weaker winds across the remainder of the waters. Seas are 1-3 ft in the Gulf of California, and 4-7 ft across the remainder of the waters away from Polo. For the forecast, Major Hurricane Polo will move to 14.6N 101.6W this afternoon, 15.0N 101.8W Wed morning, 15.7N 102.5W Wed afternoon, 16.4N 103.7W Thu morning, 17.0N 105.2W Thu afternoon, and 17.4N 106.8W Fri morning. Polo will change little in intensity as it moves to 18.2N 109.7W early Sat. 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 gradually approach the waters just beyond the Baja California offshore waters by the end of the upcoming weekend. Outer swells associated with Odalys will propagate into the Baja California waters and mix with those from Polo to create very confused and hazardous seas this weekend. Fresh to strong northerly gap winds may develop in the Gulf of Tehuantepec early Thu, then pulse into the upcoming weekend. 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, except slight seas nearshore Colombia, eastern Panama and in the lee of the Galapagos Islands. Very active convection is present across much of the offshore waters due to a passing tropical wave described above. Locally higher winds and seas may be in and near any convection. For the forecast, moderate or weaker winds are expected to prevail across the offshore waters for the next several days, except becoming moderate to fresh offshore El Salvador and Guatemala Thu into early Sat as an area of low pressure may form just west of the area. ...REMAINDER OF THE AREA... Please see the Special Features section above for details on rapidly intensifying Major Hurricane Polo, and on Tropical Storm Odalys. Outside of Odalys and Polo, fresh to strong winds, and rough seas, are over the waters from 14N to 24N and west of 133W due to a tight gradient between high pressure over the northwest portion of the area, Odalys and a remnant low pressure west of 140W. Moderate or weaker winds and moderate seas prevail elsewhere. For the forecast, Major Hurricane Polo will move to 14.6N 101.6W this afternoon, 15.0N 101.8W Wed morning, 15.7N 102.5W Wed afternoon, 16.4N 103.7W Thu morning, 17.0N 105.2W Thu afternoon, and 17.4N 106.8W Fri morning. Polo will change little in intensity as it moves to 18.2N 109.7W early Sat. Meanwhile, Tropical Storm Odalys will strengthen to a hurricane near 15.1N 130.2W this afternoon, move to 15.3N 129.3W Wed morning, 15.4N 128.0W Wed afternoon, 15.8N 126.6W Thu morning, 16.3N 125.3W Thu afternoon, and 17.0N 124.4W Fri morning. Odalys will weaken to a tropical storm over 18.5N 123.2W early Sat. Very large seas generated by both systems will merge by the end of the week into the upcoming weekend as the systems get closer together resulting in very dangerous and hazardous conditions. Otherwise, high pressure over the remainder of the area will pretty much maintain moderate or weaker winds and moderate seas.