Issued at 300 PM CST Fri Jun 13 2025
832 WTPZ44 KNHC 132032 TCDEP4 Tropical Storm Dalila Discussion Number 5 NWS National Hurricane Center Miami FL EP042025 300 PM CST Fri Jun 13 2025 Satellite images and recent ASCAT data show that Dalila is a large tropical storm with its 34-kt wind radii spread out over a broad area, especially east of the center. The ASCAT passes showed tropical-storm-force winds occurring very near the coast of southern Mexico, which are likely aided by the local terrain. The initial intensity of the storm remains 35 kt based on the aforementioned ASCAT data and a Dvorak estimate from TAFB. Dalila is the second earliest fourth named storm in the eastern Pacific basin since records began in 1949, behind 1956. Dalila likely will strengthen during the next day or so while it remains over warm waters and in a low to moderate wind shear environment. However, rapid intensification is not expected given the large size of the storm's wind field and the lack of an inner core. The opportunity for strengthening should end by late Saturday when Dalila is expected to cross the 26 C SST isotherm. Thereafter, a combination of cool waters and stable air should cause rapid weakening, and Dalila is now forecast to become a post-tropical cyclone by late Sunday. The NHC intensity forecast is similar to the previous one and near the high end of the model guidance. The storm is still moving north-northwestward at about 12 kt. A gradual turn to the northwest and then the west is expected over the next few days as Dalila moves on the south side of a building mid-level ridge. There is high confidence that the center of the system should stay off the coast of Mexico, but the northern extent of the tropical-storm-force winds are expected to brush the southwestern coast of Mexico tonight and Saturday. The NHC track forecast is a touch north of the previous one and near the middle of the guidance envelope. KEY MESSAGES: 1. The outer bands of Tropical Storm Dalila could bring locally heavy rainfall to the Mexican states of Guerrero, Michoacán, and Colima through this weekend. Isolated flooding and mudslides, especially in areas of steep terrain, are possible. 2. Dalila is expected to produce tropical-storm-force winds across portions of the warning area tonight and Saturday. FORECAST POSITIONS AND MAX WINDS INIT 13/2100Z 14.8N 102.4W 35 KT 40 MPH 12H 14/0600Z 15.7N 103.5W 45 KT 50 MPH 24H 14/1800Z 16.8N 105.1W 55 KT 65 MPH 36H 15/0600Z 17.8N 107.0W 55 KT 65 MPH 48H 15/1800Z 18.4N 108.9W 45 KT 50 MPH 60H 16/0600Z 18.5N 110.9W 35 KT 40 MPH...POST-TROPICAL 72H 16/1800Z 18.5N 112.7W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 17/1800Z 18.5N 115.4W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 18/1800Z...DISSIPATED $$ Forecaster Cangialosi