Tropical Cyclone Discussion
839 WTPZ42 KNHC 260853 TCDEP2 Hurricane Polo Discussion Number 23 NWS National Hurricane Center Miami FL EP172026 200 AM MST Sat Sep 26 2026 The NOAA aircraft that flew in Polo from 25/22Z to 26/01Z found maximum flight-level winds of 154 kt, corresponding to about 140 kt surface winds using standard reduction factors. Since that time, the structure of Polo has continued to look very impressive on satellite imagery. The eye has become a bit more cloud-filled with cooling infrared eye temperatures only over the last hour or two. The latest intensity estimate from TAFB is 7.5/155 kt and latest objective estimates from UW-CIMSS range from 133-153 kt. The ADT estimate of 167 kt looks a bit unrealistically too high, given some of the other observed data. Based on the earlier recon data and the recent cooling observed in the eye, the intensity is nudged downward slightly to 145 kt. Polo is expected to remain in a favorable environment for another 48 hours although sea-surface temperatures and ocean heat content will begin decreasing after hour 24. As Polo approaches Baja California Sur, increasing southwesterly wind shear is expected to cause a faster rate of weakening. The NHC intensity forecast is near the high end of the model guidance suite through 48 hours. Thereafter, the NHC forecast lies between the middle and high end of the guidance. Polo is expected to be a powerful hurricane when it reaches Baja California Sur, and it likely to still be a hurricane when it reaches mainland northwestern Mexico. The initial motion estimate is west-northwestward, or 290 degrees at 8 kt. There is no change to the track forecast reasoning with this advisory. The hurricane is expected to turn gradually northwestward tomorrow, then northward by the end of the weekend while it moves around the western side of a ridge centered over northern Mexico. Early next week an upper-level trough approaching from the northwest will cause the hurricane to turn northeastward toward Baja California Sur and west-central Mexico. The NHC track forecast is very similar to the previous advisory, and is slightly slower than the latest HCCA and GDMI, but much faster than the latest TVCN consensus. The track guidance is good agreement in that there is very little cross-track spread. However, there are still some timing differences (quite a bit of along-track spread). With this in mind, residents in Baja California Sur and northwestern Mexico should consider finishing their preparations by Sunday. Distant moisture from Hurricane Polo and Odalys will be transported into the southwestern United States this weekend and early next week, and may indirectly contribute to a heavy rainfall and flash flood threat in the region. See products issued by the Weather Prediction Center for more information. Key Messages: 1. Polo is forecast to approach the west coast of the Baja California peninsula on Monday as a hurricane, and a Hurricane Watch is in effect for that region. Tropical Storm conditions could reach portions of the coast as soon as late Sunday, making further preparations difficult. A storm surge will be possible, especially in areas of onshore winds. 2. Heavy rainfall associated with Polo may begin to impact Baja California Sur late Sunday into Monday. This rainfall may produce life-threatening flooding and mudslides, especially in areas of steep terrain. 3. Dangerous surf and rip currents are likely along portions of the northwest coast of Mexico and Baja California for the next several days. FORECAST POSITIONS AND MAX WINDS INIT 26/0900Z 17.6N 111.0W 145 KT 165 MPH 12H 26/1800Z 18.3N 112.1W 145 KT 165 MPH 24H 27/0600Z 19.7N 113.3W 135 KT 155 MPH 36H 27/1800Z 21.5N 113.8W 125 KT 145 MPH 48H 28/0600Z 23.4N 113.8W 110 KT 125 MPH 60H 28/1800Z 25.1N 113.2W 95 KT 110 MPH 72H 29/0600Z 26.9N 111.6W 75 KT 85 MPH 96H 30/0600Z 30.3N 107.5W 30 KT 35 MPH...INLAND 120H 01/0600Z...DISSIPATED