Hurricane Polo Forecast Discussion
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Español: Aviso Publico Discusión |
000 WTPZ42 KNHC 271457 TCDEP2 Hurricane Polo Discussion Number 28 NWS National Hurricane Center Miami FL EP172026 800 AM MST Sun Sep 27 2026 Polo continues to have a pretty healthy structure on geostationary satellite imagery this morning, with very cold cloud tops associated with robust eyewall convection. The most recent F18 SSMIS microwave pass showed a mostly closed eyewall, albeit with some erosion on the east side, likely due to some residual easterly vertical wind shear. Both the subjective and objective intensity estimates over the past 6 h have increased somewhat, with the latest SATCON, DPRINT, and DMINT estimates between 106-113 kt. Thus, the initial intensity is nudged up slightly to 110 kt for this advisory. A NOAA P-3 Hurricane Hunter aircraft is currently en route and will provide updated in-situ data on Polo this afternoon. Polo continues to make its turn more northward, with the latest estimated motion at 345 degrees at 10 kt. The hurricane should soon turn northward and the northeastward over the next 12-24 h as it is steered between the deep-layer ridging that is centered over Mexico and a mid-latitude shortwave trough that will soon move into California. It is this short-wave that is expected to capture Polo as it reaches the coast of Baja California Sur, leading to further acceleration as the hurricane turns northeastward. While the track guidance this cycle is very tightly clustered near the previous forecast track, but are somewhat faster along this track. Thus the latest NHC track forecast has been moved slightly faster and roughly splits the difference between the reliable HFIP Corrected Consensus Approach (HCCA) and Google DeepMind ensemble mean (GDMI) aids. Its is worth noting there remains some along-track spread in the ensemble guidance, so the exact timing of landfall is more uncertain than usual in the 24-48 h time frame. The intensity forecast also has some challenges. Polo has maintained a fairly healthy appearance while its been dealing with light to moderate easterly vertical wind shear. The latest SHIPS guidance now shows the shear decreasing over the next 12-24 h, and given the slightly stronger initial intensity, the latest NHC intensity forecast is higher than the previous one. This forecast is on the high end of the interpolated intensity guidance, and now shows Polo reaching the coast of the Baja California Peninsula as a 95 kt hurricane. It is worth mentioning the latest HAFS-B raw model output shows Polo could retain major hurricane intensity at landfall. Some weakening should occur as it moves over the rugged terrain of Baja California, but it is increasingly likely that Polo's second landfall in mainland Mexico will also be as a (weaker) hurricane. Rapid weakening is forecast thereafter as it moves inland over Mexico with Polo becoming post-tropical or dissipating by 72 h. Polo is expected to become a remnant low and then dissipate before it reaches the southern U.S., but distant moisture associated with it and Odalys will be transported into the southwestern United States late 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 Warning is in effect for that region. Tropical storm conditions could reach portions of the coast as soon as tonight or early Monday, making further preparations difficult. These conditions will likely spread across Baja California through Monday. A storm surge is likely, especially in areas of onshore winds. 2. Heavy rainfall associated with Polo may begin to impact Baja California Sur tonight into Tuesday. 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 few days. FORECAST POSITIONS AND MAX WINDS INIT 27/1500Z 21.3N 113.9W 110 KT 125 MPH 12H 28/0000Z 22.7N 113.9W 110 KT 125 MPH 24H 28/1200Z 24.5N 113.4W 105 KT 120 MPH 36H 29/0000Z 26.3N 112.2W 95 KT 110 MPH 48H 29/1200Z 28.6N 110.0W 55 KT 65 MPH 60H 30/0000Z 31.5N 107.2W 30 KT 35 MPH...POST-TROP/INLAND 72H 30/1200Z...DISSIPATED $$ Forecaster Papin