ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM Tropical Storm Lorena Discussion Number 5 NWS National Hurricane Center Miami FL EP152019 1000 AM CDT Wed Sep 18 2019 Lorena's cloud pattern has improved this morning, with the development of a central dense overcast feature, and several bands wrapping around the circulation. The initial intensity has been increased to 55 kt, which is in agreement subjective satellite estimates from SAB, and objective estimates from UW/CIMSS. Lorena is located within favorable oceanic and atmospheric conditions, and additional strengthening is forecast during the next 12 to 24 hours. After that time, Lorena's intensity will depend on how much interaction occurs with the mountainous terrain of southwestern Mexico. The latest NHC forecast takes the center along the immediate coast and shows some slight weakening as this occurs. After that time, re-strengthening is possible as Lorena is forecast to traverse warm waters to the southeast of the Baja California peninsula. It should be noted that the intensity forecast is more uncertain than normal due to the potential for land interaction. Lorena has moved a little right of the previous track. Recent microwave fixes indicated a northwestward motion of 325/11 kt. Lorena is forecast to move northwestward around the southwestern portion of mid-level ridge. The overall track envelope has nudged eastward, closer to the coast of southwestern Mexico. In fact, the ECMWF brings the center of Lorena onshore tonight, and that is a distinct possibility. The early portion of the NHC track has been nudged eastward, and lies between the aforementioned ECMWF model track and the various consensus aids. After 24 hours, most of the guidance turns Lorena west-northwestward as a narrow ridge builds to the north of the cyclone. During this portion of the track forecast, the guidance has shifted to the right, and the NHC forecast has been adjusted accordingly. Key Messages: 1. Lorena is forecast to become a hurricane and move dangerously close to the coast of southwestern Mexico later today and tonight. A hurricane warning has been issued for this area and preparations to protect life in property should be rushed to completion. 2. Lorena is forecast to cause heavy rain over portions of the Mexican states of Guerrero, Michoacan, Colima, and Jalisco during the next few days. This rainfall may produce life-threatening flash flooding and mudslides. FORECAST POSITIONS AND MAX WINDS INIT 18/1500Z 17.4N 103.5W 55 KT 65 MPH 12H 19/0000Z 18.6N 104.4W 65 KT 75 MPH 24H 19/1200Z 19.8N 105.4W 70 KT 80 MPH 36H 20/0000Z 20.5N 106.2W 60 KT 70 MPH 48H 20/1200Z 21.2N 107.4W 65 KT 75 MPH 72H 21/1200Z 22.4N 110.0W 65 KT 75 MPH 96H 22/1200Z 24.0N 112.4W 55 KT 65 MPH 120H 23/1200Z 26.7N 114.2W 40 KT 45 MPH $$ Forecaster Brown NNNN