ZCZC MIATCDEP3 ALL TTAA00 KNHC DDHHMM Tropical Depression Thirteen-E Discussion Number 1 NWS National Hurricane Center Miami FL EP132023 800 AM PDT Tue Sep 19 2023 Persistent showers and thunderstorms have become better organized in association with the area of low pressure located several hundred miles southwest of the southern tip of Baja California. A 19/0535 UTC ASCAT-C pass showed a well-defined circulation. The invest is upgraded to a 30-kt tropical depression. This intensity is in agreement with the ASCAT pass and a satellite intensity estimate of 30 kt from TAFB. The current motion estimate is 295/11. A west-northwestward motion is expected during the next 36 h as the cyclone is steered by the trade wind flow. After that time, a potent mid- to upper-level trough approaching from the northwest is expected to cause Thirteen-E to turn to the northwest and north-northwest. The track forecast is in best agreement with the consensus aid TVCE. After the cyclone loses its convection and becomes a remnant low, a bend back to the west-northwest is likely in 4 to 5 days. Warm ocean temperatures, light northeasterly to easterly vertical wind shear, and a moist low to mid-level troposphere currently surround the tropical cyclone. The system has perhaps 36 hours to strengthen while it remains over these relatively favorable environmental conditions. The cyclone is forecast to cross the 26C isotherm in about 48 h. The aforementioned approaching mid- to upper-level trough will induce strong southwesterly vertical wind shear on the cyclone beginning by 60 h. After that time, much drier air along with further decreasing ocean temperatures and increasing wind shear will lead to the cyclone losing its convection and becoming a remnant low in about 4 days. FORECAST POSITIONS AND MAX WINDS INIT 19/1500Z 15.0N 119.0W 30 KT 35 MPH 12H 20/0000Z 15.2N 120.7W 35 KT 40 MPH 24H 20/1200Z 15.5N 122.5W 35 KT 40 MPH 36H 21/0000Z 16.0N 123.9W 40 KT 45 MPH 48H 21/1200Z 16.7N 125.2W 35 KT 40 MPH 60H 22/0000Z 17.9N 126.2W 30 KT 35 MPH 72H 22/1200Z 19.8N 127.0W 30 KT 35 MPH 96H 23/1200Z 22.5N 127.6W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 24/1200Z 24.0N 129.5W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ Forecaster Hagen/Reinhart NNNN