Tropical Cyclone Discussion
541 WTPZ41 KNHC 170845 TCDEP1 Hurricane Trudy Discussion Number 16 NWS National Hurricane Center Miami FL EP212026 300 AM CST Sat Oct 17 2026 Trudy's satellite presentation has changed little overall during the past several hours, although the curved band of deep convection wrapping around the northern semicircle has expanded somewhat, with cloud tops as cold as -85 degrees C. A 0053 UTC RCM-3 synthetic aperture radar (SAR) pass and a 0439 UTC Metop-B scatterometer pass helped refine the initial position and wind radii of the hurricane. The latest subjective Dvorak intensity estimate from TAFB and objective satellite estimates remain near 75 kt. Given the relatively steady intensity estimates and only modest changes in the convective organization, the initial intensity is held at 80 kt. The initial motion is northwestward, or 325/7 kt. A continued northwestward motion at a slightly faster forward speed is expected during the next day or so as a weak low- to mid-level ridge builds over eastern Mexico. This general motion should continue through Sunday, bringing the center of Trudy very close to the coast of west-central Mexico. Thereafter, as Trudy weakens and becomes increasingly influenced by the low-level steering flow, a turn toward the west-northwest is expected, taking the cyclone away from the coast early next week. The latest NHC track forecast has been adjusted slightly to the left of the previous prediction, but remains along the right side of the track guidance envelope during the time of closest approach to the coast of Mexico. While Trudy remains over warm waters with relatively high ocean heat content, some additional strengthening is possible today. However, moderate vertical wind shear, estimated at around 14 kt by the latest UW-CIMSS analysis, along with possible dry-air entrainment and the cyclone's proximity to the coast of Mexico, could limit further intensification. By late Sunday, increasing southwesterly vertical wind shear and a progressively drier mid-level environment are expected to induce steady weakening. The latest SHIPS guidance indicates that shear could increase to around 20 to 25 kt by early next week, while mid-level relative humidity decreases to below 50 percent. These increasingly hostile conditions should eventually cause Trudy to lose its organized deep convection, with the cyclone forecast to become a post-tropical remnant low by day 4 and dissipate by day 5. The latest NHC intensity forecast is very similar to the previous prediction, lying near the upper end of the guidance envelope. KEY MESSAGES: 1. Trudy could strengthen some during the next 12 hours as it approaches the coast of southwestern and west-central Mexico this weekend, bringing an increasing risk of storm surge, damaging winds, and flooding rain. Hurricane Warnings and Watches, as well as Tropical Storm Warnings and Watches, are currently in effect for portions of the coast, and additional watches and warnings may be required. 2. Heavy rainfall associated with Trudy will impact the southwest Mexican coast between Guerrero and Nayarit through the weekend. This rainfall may produce life-threatening flooding and mudslides along and near the southwest Mexican coast in Michoacán, Colima, and Jalisco, especially in areas along steep terrain. 3. Large swells are affecting portions of the coast of southwestern Mexico and will spread northward through the weekend, causing life-threatening surf and rip current conditions. FORECAST POSITIONS AND MAX WINDS INIT 17/0900Z 16.0N 103.4W 80 KT 90 MPH 12H 17/1800Z 17.1N 104.2W 90 KT 105 MPH 24H 18/0600Z 18.6N 105.4W 90 KT 105 MPH 36H 18/1800Z 19.7N 106.1W 85 KT 100 MPH 48H 19/0600Z 20.5N 106.9W 70 KT 80 MPH 60H 19/1800Z 20.7N 107.4W 55 KT 65 MPH 72H 20/0600Z 20.9N 108.1W 40 KT 45 MPH 96H 21/0600Z 21.1N 109.3W 30 KT 35 MPH...POST-TROP/REMNT LOW 120H 22/0600Z...DISSIPATED