Tropical Cyclone Discussion
318 WTPZ41 KNHC 150838 TCDEP1 Hurricane Trudy Discussion Number 8 NWS National Hurricane Center Miami FL EP212026 300 AM CST Thu Oct 15 2026 Trudy's satellite presentation continues to improve, with an expanding central dense overcast containing cloud tops as cold as -85 degrees C and a curved convective band wrapping into the circulation from the north. Earlier microwave passes revealed improving inner-core organization, while a 0339 UTC MetOp-B scatterometer pass helped refine the cyclone's wind radii and structure. The latest subjective Dvorak intensity estimate from TAFB is T4.0/65 kt, which is consistent with the latest objective estimates. Based on these data, the initial intensity is increased to 65 kt, making Trudy a category 1 hurricane on the Saffir-Simpson Hurricane Wind Scale. The initial motion is northwestward, or 305/8 kt. A gradual turn toward the north-northwest is expected during the next day or so as the mid-level ridge extending across central Mexico weakens in response to an amplifying mid- to upper-level trough over the Gulf of America. Some interaction with Tropical Storm Simon, a compact tropical cyclone located several hundred miles to the northwest, could also influence Trudy's steering. This pattern is expected to bring Trudy very close to the coast of southwestern and west-central Mexico over the weekend, from near Punta San Telmo to Cabo Corrientes, before a rebuilding ridge to the north induces a westward turn away from the coast early next week. Considerable track uncertainty remains, particularly from days 4 to 5, when the guidance continues to show a significant amount of cross-track spread. The latest NHC track forecast is essentially unchanged from the previous prediction through 72 h, with another slight adjustment to the north at days 4 and 5 as Trudy turns westward away from the coast. The forecast closely follows the latest HCCA and GDMI consensus aids. Environmental conditions remain quite favorable for significant strengthening during the next couple of days, with very low vertical wind shear, warm sea surface temperatures, and plenty of deep moisture surrounding Trudy. The continued improvement in Trudy's convective structure and inner-core organization suggests that the hurricane could be poised to undergo a period of rapid intensification (RI). This possibility is supported by the latest SHIPS RI guidance, which indicates a 28 to 40 percent probability of a 35-kt increase in maximum winds during the next 24 h, roughly four to six times the climatological mean. Although Trudy could briefly encounter lower ocean heat content associated with the wakes of previous tropical cyclones, oceanic conditions are forecast to become more favorable thereafter. The NHC intensity forecast calls for RI during the next 24 h, with Trudy expected to become a major hurricane by Friday, followed by additional strengthening through Saturday. By day 3, increasing vertical wind shear and the entrainment of drier mid-level air are expected to induce weakening. The NHC intensity forecast remains above the guidance envelope during the next few days, then lies near the upper end of the guidance envelope thereafter. Trudy is forecast to approach the coast of southwestern and west-central Mexico as a major hurricane this weekend. Tropical-storm-force winds could reach portions of the coast as early as Saturday, and watches will likely be required for portions of the coast later this morning. Interests along the coast of southwestern and west-central Mexico should closely monitor the progress of Trudy and be prepared to implement their hurricane plans. KEY MESSAGES: 1. Trudy is forecast to be a major hurricane as it approaches the coast of southwestern and west-central Mexico this weekend. There is an increasing risk of wind, rain, and storm surge impacts, and watches will likely be required for portions of the coast later this morning. 2. Heavy rainfall associated with Trudy will impact the southwest coast of Mexico between Guerrero and Jalisco through the weekend. This rainfall may produce life-threatening flooding and mudslides by the weekend across Colima and Jalisco, especially in areas along steep terrain. 3. Large swells will begin to affect portions of the coast of southwestern Mexico Friday and continue through the weekend. These swells could cause life-threatening surf and rip current conditions. FORECAST POSITIONS AND MAX WINDS INIT 15/0900Z 12.9N 101.6W 65 KT 75 MPH 12H 15/1800Z 13.4N 101.9W 80 KT 90 MPH 24H 16/0600Z 14.2N 102.3W 100 KT 115 MPH 36H 16/1800Z 15.1N 102.8W 110 KT 125 MPH 48H 17/0600Z 16.1N 103.4W 115 KT 130 MPH 60H 17/1800Z 17.4N 104.4W 115 KT 130 MPH 72H 18/0600Z 18.8N 105.5W 105 KT 120 MPH 96H 19/0600Z 20.5N 107.3W 75 KT 85 MPH 120H 20/0600Z 20.7N 108.5W 60 KT 70 MPH