ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM Tropical Storm Lorena Discussion Number 3 NWS National Hurricane Center Miami FL EP152019 1000 PM CDT Tue Sep 17 2019 There has been little change in the cloud structure of Lorena since the last advisory, with the storm having a central convective feature and a ragged band in the western semicircle. A recently- received WindSat overpass indicates the low-level center is located near the northwestern edge of the central convection. The initial intensity remains 45 kt in good agreement with a subjective satellite estimate from TAFB. The initial motion is 305/13. A mid- to upper-level ridge over Mexico should steer Lorena generally northwestward with some decrease in forward speed during the forecast period, with the center likely to pass near the southwestern coast of Mexico late Wednesday through Thursday. The guidance has shifted a little to the left since the last advisory, and the new forecast track keeps the center of Lorena a little farther offshore than than the previous forecast. However, any motion to the right of the track would bring the center onshore in southwestern Mexico and cause rapid dissipation. If the center stays offshore, Lorena is forecast to be near the southern portion of the Baja California peninsula by the end of the forecast period. Conditions appear favorable for slow strengthening as Lorena approaches the southwestern coast of Mexico. Based on the forecast track now staying offshore, the new intensity forecast calls for a stronger storm by 48-72 h, with Lorena now forecast to be just under hurricane strength. This peak would be followed by a weakening trend as Lorena gradually moves over cooler water. An alternative intensity forecast is for Lorena to dissipate if the center moves onshore in southwestern Mexico. Key Messages: 1. 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. 2. Tropical storm conditions are expected along a portion of the southwestern coast of Mexico by late Wednesday. FORECAST POSITIONS AND MAX WINDS INIT 18/0300Z 15.1N 102.1W 45 KT 50 MPH 12H 18/1200Z 16.3N 103.0W 50 KT 60 MPH 24H 19/0000Z 17.7N 104.0W 50 KT 60 MPH 36H 19/1200Z 18.6N 104.7W 55 KT 65 MPH 48H 20/0000Z 19.3N 105.4W 60 KT 70 MPH 72H 21/0000Z 20.6N 107.3W 60 KT 70 MPH 96H 22/0000Z 22.0N 110.0W 55 KT 65 MPH 120H 23/0000Z 24.5N 112.5W 45 KT 50 MPH $$ Forecaster Beven NNNN