Issued at 200 PM MST Tue Oct 07 2025
000 WTPZ41 KNHC 072038 TCDEP1 Hurricane Priscilla Discussion Number 13 NWS National Hurricane Center Miami FL EP162025 200 PM MST Tue Oct 07 2025 Priscilla's structure hasn't changed much from 6 hours ago. The hurricane continues to display a large eye, about 50 n mi in diameter. A ring of convection with cloud tops colder than -60 degrees C completely surrounds the eye at a radius of about 40 n mi. Earlier, a ring with cloud tops colder than -70C briefly surrounded the eye. The eye itself is a bit messy with low clouds seen on GOES-18 1-minute imagery swirling inside. The latest subjective and objective intensity estimates are mostly ranging from 95-108 kt. Given the large and broad nature of the eye and eyewall, the initial intensity is maintained at 95 kt, near the lower end of the satellite estimates. Over the next 12 hours, Priscilla should maintain its intensity or possibly strengthen slightly while the hurricane remains over warm waters and in a moist, moderate shear environment. After that, the hurricane is forecast to move over progressively cooler waters, reaching the 26 degree C sea-surface temperature isotherm in 36 hours. Priscilla will also be moving into a drier environment as it gains latitude. Therefore, the NHC forecast calls for weakening beginning Wednesday. Southwesterly vertical wind shear is forecast to increase over the cyclone in 3 days, and simulated satellite images from the GFS and ECMWF models indicate that Priscilla should lose its convection and become a remnant low shortly after 72 hours, before the system reaches the Baja California peninsula. Enhanced moisture is likely to be transported northward over portions of the southwestern U.S. late this week, resulting in the potential for heavy rainfall. The hurricane has jogged toward the west-northwest over the past 6 hours, and the initial motion estimate is 295 degrees at 8 kt. A general northwestward motion is expected through Thursday as Priscilla moves around the southwestern periphery of a mid-level ridge over northern Mexico. Priscilla is forecast to move parallel to, but remain offshore of, the southern Baja California peninsula through Thursday. By Thursday night, an amplifying trough off the U.S. West Coast is forecast to erode the steering ridge to the north of Priscilla. The weakness in the ridge should induce a northward turn later this week and into the weekend. The track models are still in fairly good agreement through about 60 h, but there are still some speed differences in the guidance after that time, as Priscilla weakens to a remnant low. The new NHC track forecast is slightly to the left of the previous one through 36 h, mainly due to the farther west initial position. Thereafter, the new official forecast is on top of the previous one, and lies in between the latest GFEX and HFIP Corrected Consensus (HCCA) solutions. KEY MESSAGES: 1. Tropical storm conditions are possible along the Baja California Sur Pacific coastline within the Tropical Storm Watch area tonight into Wednesday. Interests elsewhere in the Baja California peninsula should monitor the progress of Priscilla. 2. Heavy rainfall associated with Priscilla will impact portions of Baja California Sur tonight into Wednesday. Its moisture will lead to heavy rainfall across west-central Mexico from today into Thursday morning and across the Desert Southwest from late this week into this weekend, which could result in flash flooding, particularly in areas of higher terrain. 3. Swells generated by Priscilla are affecting portions of the coast of southwestern and west-central Mexico as well as the coast of the southern Baja California peninsula. These swells are likely to cause life-threatening surf and rip current conditions, in addition to some coastal flooding. FORECAST POSITIONS AND MAX WINDS INIT 07/2100Z 19.9N 110.8W 95 KT 110 MPH 12H 08/0600Z 20.7N 111.9W 95 KT 110 MPH 24H 08/1800Z 21.8N 113.2W 80 KT 90 MPH 36H 09/0600Z 22.9N 114.4W 65 KT 75 MPH 48H 09/1800Z 24.2N 115.2W 55 KT 65 MPH 60H 10/0600Z 25.5N 115.5W 45 KT 50 MPH 72H 10/1800Z 26.7N 115.4W 35 KT 40 MPH 96H 11/1800Z 29.3N 114.5W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 12/1800Z...DISSIPATED $$ Forecaster Hagen
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