000 WTPZ44 KNHC 182035 TCDEP4 Tropical Storm Dolores Discussion Number 3 NWS National Hurricane Center Miami FL EP042021 400 PM CDT Fri Jun 18 2021 Dolores is a large, sprawling tropical storm. Recent scatterometer data indicated that the circulation remains broad, with the center embedded within an elongated area of lighter winds. However, the scatterometer passes also showed an extensive area of tropical-storm-force winds extending up to 140 n mi to the northeast of the center, blowing from east to west away from the coast of Mexico. Based on these data, Dolores's initial winds are set at 40 kt. The ASCAT data indicated that Dolores's center is located a little farther to the right, or northeast, of the previous NHC track forecast. With this adjusted position, the initial motion is now estimated to be northwestward (310 degrees) at 6 kt. Dolores is moving around the western periphery of a mid-level ridge which extends across the northwestern Caribbean Sea and southeastern Mexico, and this feature should steer the storm northwestward to north-northwestward during the next couple of days. All of the reliable track models show this general trajectory, and they bring the center inland along the coast of Michoacan, Colima, or Jalisco during within the next 18-36 hours, with the timing depending on the storm's exact heading. Because of the eastward adjustment of the initial position, the new NHC track forecast has been shifted eastward, but it still generally follows the TVCE and HCCA consensus aids. Environmental conditions are generally conducive for additional strengthening, particularly warm sea surface temperatures, mid-level relative humidity between 70 and 80 percent, and significant upper-level divergence. The two limiting factors to intensification are (1) the broad structure of the circulation and (2) less potential time over water due to the eastward shift in the track. The updated NHC intensity forecast continues to show intensification up until landfall and is generally close to the IVCN and HCCA consensus aids. There is still some possibility that Dolores could be near hurricane strength when it reaches the coast if the intensification rate is faster than indicated in the forecast, or if the center ends up staying over water longer than indicated. After the center crosses the coast, the mountainous terrain of west-central Mexico should cause rapid weakening, with the cyclone degenerating into a remnant low, and then completely dissipating, in 2 to 3 days. Key Messages: 1. Dolores is expected to continue strengthening tonight and on Saturday, and it could be near hurricane strength when it reaches the coast of west-central Mexico by Saturday afternoon. A tropical storm warning and a hurricane watch are in effect for portions of the southwestern and west-central coasts of Mexico. 2. Heavy rains are forecast over coastal sections of the Mexican states of Oaxaca, Guerrero, Michoacan, Colima, Jalisco, and Nayarit during the next few days, which could result in life-threatening flash flooding and mudslides. FORECAST POSITIONS AND MAX WINDS INIT 18/2100Z 15.6N 102.3W 40 KT 45 MPH 12H 19/0600Z 16.6N 103.1W 50 KT 60 MPH 24H 19/1800Z 18.5N 104.0W 55 KT 65 MPH 36H 20/0600Z 21.2N 104.7W 35 KT 40 MPH...INLAND 48H 20/1800Z 23.6N 105.4W 25 KT 30 MPH...POST-TROP/INLAND 60H 21/0600Z...DISSIPATED $$ Forecaster Berg