Issued at 800 AM MST Mon Sep 28 2026
000 WTPZ42 KNHC 281446 TCDEP2 Hurricane Polo Discussion Number 32 NWS National Hurricane Center Miami FL EP172026 800 AM MST Mon Sep 28 2026 On geostationary satellite, Polo still looks pretty healthy, with a small central dense overcast with an embedded eye, though the eye feature has been coming and going. Some of this evolution is likely due to inner-core structural changes near the center, where an earlier AMSR-3 microwave pass at 0928 UTC showed evidence of concentric rings suggesting an eyewall replacement cycle (ERC) on the 37 GHz channel. The 12 UTC subjective Dvorak TAFB CI number remains 5.5/102 kt, though the objective intensity estimates have fallen some. For now, the initial intensity is being maintained at 100 kt, pending another NOAA P-3 aircraft that should provide an update in the storms structure and intensity this afternoon. Polo appears to be making the turn to the northeast, with the estimated motion now at 35 degrees at 9 kt. This general heading in Polo's track should continue for the next 36 h, though with some gradual acceleration as the hurricane is captured by a short-wave trough swinging into the southwestern United States. This track will take Polo's core over the Baja California Peninsula this evening, then briefly moving over the Gulf of California overnight wit ha second landfall in northwestern mainland Mexico on Tuesday Morning. The latest NHC track forecast is very close to the previous one, following the reliable HFIP corrected consensus approach (HCCA) and Google DeepMind ensemble mean (GDMI). The vertical wind shear remains low over Polo at the moment, and has now shifted out of the southwest, so the vector is in the same direction as its component of motion. In addition sea-surface temperatures actually warm as the hurricane approaches the coastline. Thus, Polo's intensity will be primarily governed by inner-core structural changes today before landfall. While the interpolated guidance shows a bit of modest weakening in 12 h, given the favorable environment, it is probably more prudent to maintain the hurricane's current intensity before it makes landfall in the Baja California Peninsula where it will likely be near or at major hurricane intensity. Land interaction with the peninsula and shear increasing should lead to significant weakening, but Polo is still expected to be a hurricane when it reaches mainland Mexico. Even more rapid weakening is expected when Polo moves inland over the high rugged terrain of northwestern mainland Mexico and the storm will likely dissipate over the higher terrain long before it reaches the southwestern U.S. Although Polo is expected to dissipate before it reaches the southern U.S., distant moisture associated with it and the Post- Tropical Cyclone Odalys will be transported into the southwestern United States during the next few days, 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 make landfall on the west coast of the Baja California Peninsula near major hurricane strength this evening. Conditions will deteriorate shortly, making preparations difficult. Hurricane and tropical storm conditions are expected to spread across Baja California through tonight, and into mainland Mexico late on early Tuesday. A dangerous storm surge is likely in areas of onshore winds. 2. Heavy rainfall from Polo will impact Baja California Sur and southern and central portions of Sonora today into Tuesday. This rainfall may produce life-threatening flooding and mudslides, especially in areas of steep terrain. Moisture from Polo will support heavy rainfall and flooding potential across the southwest U.S. into the southern High Plains late today into Tuesday. 3. Even after Polo dissipates, its mid-level remnants may produce gusty winds well inland over the higher terrain of northwest Mexico and the southwest United States. 4. Dangerous surf and rip currents are likely along portions of the northwest coast of Mexico and Baja California for the next couple of days. FORECAST POSITIONS AND MAX WINDS INIT 28/1500Z 24.2N 113.5W 100 KT 115 MPH 12H 29/0000Z 25.4N 112.7W 100 KT 115 MPH 24H 29/1200Z 27.4N 111.0W 70 KT 80 MPH...OVER WATER 36H 30/0000Z 29.9N 108.8W 30 KT 35 MPH...POST-TROP/INLAND 48H 30/1200Z...DISSIPATED $$ Forecaster Papin
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