Issued at 200 PM MST Mon Sep 28 2026
042 WTPZ42 KNHC 282052 TCDEP2 Hurricane Polo Discussion Number 33 NWS National Hurricane Center Miami FL EP172026 200 PM MST Mon Sep 28 2026 NOAA Hurricane Hunters investigated Polo this afternoon, finding the hurricane was still well organized with a 23 n mi wide eye, though the eyewall was open to the southwest and there was a subtle increase in the vertical tilt comparing the 1-5 km Tail Doppler Radar (TDR) wind data from the aircraft. The highest 700 mb flight-level winds were 106 kt in the southeast quadrant, which using a typical 0.9 reduction factor would suggest an intensity of 95 kt. However, the TDR data has also been useful to diagnose the intensity of Polo since it samples a larger wind field swath, and the final southwest to northeast leg through the hurricane indicated 0.5 km winds up to 112 kt in the northeast eyewall. Experimental reduction data from this TDR analysis in this region reduced these boundary layer winds down to 100 kt at 10 meters. Thus, the initial intensity remains 100 kt for this advisory. Polo continues to move northeastward, but it is starting to accelerate some with an current motion of 40 degrees at 10 kt. This general motion should continue over the next day with gradual acceleration as the hurricane is captured by a strong shortwave trough swinging into the southwestern United States. This track will take Polo's core over the Baja California Peninsula this evening very close to Puerto San Andresito. The hurricane will then briefly move over the Gulf of California overnight, finally making a second landfall in northwestern mainland Mexico on Tuesday morning. The NHC track forecast is essentially an update from this morning, and is in the middle of the tightly clustered guidance. Sea-surface temperatures actually increase a bit as Polo approaches Baja California Sur. Vertical wind shear, while also increasing, is unlikely to get strong enough over the next 3-6 h to cause much weakening. Thus, Polo is likely to maintain its current intensity and be at or near major hurricane intensity when it makes landfall on the west coast of Baja California Sur this evening. Weakening will likely begin immediately after it moves over the rugged terrain of the peninsula, though Polo is still expected to be a hurricane when it makes its second landfall in mainland Mexico on the Gulf of California coast. Rapid weakening is expected when Polo moves fully inland over the high rugged terrain of northwestern Mexico, and the tropical cyclone is expected to degenerate into a trough before its remnants reach the southwestern United States. However Polo's remnant vorticity will ultimately interact and phase with a strong cutoff low digging into the the four corners region of the U.S. on Tuesday into Wednesday, contributing to heavy rainfall, flash flooding, and gusty winds the southwestern U.S. and southern Plains. See products issued by the Weather Prediction Center and local National Weather Service offices 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 quickly, and residents are urged to seek safe shelter. Hurricane and tropical storm conditions will spread inland across Baja California tonight, and into mainland Mexico late tonight and early Tuesday. A dangerous storm surge is expected in areas of onshore winds. 2. Heavy rainfall associated with Polo will impact Baja California Sur along with 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 strong gusty winds well inland over the higher terrain of northwest Mexico and southern New Mexico and far western Texas. 4. Dangerous surf and rip currents are likely along portions of the northwest coast of Mexico and Baja California for the next day or so. FORECAST POSITIONS AND MAX WINDS INIT 28/2100Z 25.0N 113.0W 100 KT 115 MPH 12H 29/0600Z 26.2N 112.1W 80 KT 90 MPH...INLAND OVER BAJA CA 24H 29/1800Z 28.7N 109.8W 40 KT 45 MPH...INLAND OVER MEXICO 36H 30/0600Z...DISSIPATED $$ Forecaster Papin
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