000 WTPZ42 KNHC 041448 TCDEP2 Tropical Depression Twelve-E Discussion Number 1 NWS National Hurricane Center Miami FL EP122022 1000 AM CDT Sun Sep 04 2022 Satellite images indicate that the area of low pressure located a couple of hundred miles south of southwestern Mexico has developed sufficently organized deep convection and a well-defined center to be classified a tropical depression. Thunderstorm activity, with a significant amount of lightning, is strongest in a band on the system's west side. The initial intensity is set at 30 kt based on a Dvorak estimate from TAFB. It should also be noted there are likely strong wind gusts to the north of the center where winds typically accelerate in these situations near the coast of Mexico. The initial motion is estimated to be 280/9 kt, but this is somewhat uncertain since the system just formed. This general motion is expected to continue for the next couple of days, keeping the core of the system south of the coast of southwestern Mexico during that time. Thereafter, the models all show a turn to the northwest and then the north. Although the models agree on this turn, there is some spread on where and how sharply the system recurves. The GFS and ECMWF ensemble spreads show solutions as far east as the Gulf of California and as far west as a few hundred miles west of the Baja California peninsula. The NHC track forecast follows the consensus models, which takes the system very near the Baja peninsula in 4 to 5 days. Overall, the environmental factors appear conducive for the depression to intensify during the next few days with the shear remaining low to moderate in strength, mid-level moisture very high, and SSTs sufficently warm. However, the large size of the system and lack of an inner core should limit rapid intensification in the short term. The intensity guidance show at least steady strengthening during the next 72 hours followed by some weakening toward the end of the forecast period due to cooler SSTs. The NHC intensity forecast is close to the IVCN guidance, and shows the system becoming a tropical storm later today and a significant hurricane near Baja in a few days. KEY MESSAGES: 1. Although the depression is expected to stay offshore, heavy rainfall could lead to localized flash flooding in portions of southwestern Mexico. 2. Interests in the Baja California peninsula should closely monitor the depression as tropical storm or hurricane watches could be required tonight. FORECAST POSITIONS AND MAX WINDS INIT 04/1500Z 14.0N 101.4W 30 KT 35 MPH 12H 05/0000Z 14.3N 103.0W 40 KT 45 MPH 24H 05/1200Z 14.6N 105.0W 50 KT 60 MPH 36H 06/0000Z 15.3N 106.8W 60 KT 70 MPH 48H 06/1200Z 16.3N 108.5W 70 KT 80 MPH 60H 07/0000Z 17.8N 110.2W 80 KT 90 MPH 72H 07/1200Z 19.6N 111.3W 85 KT 100 MPH 96H 08/1200Z 23.6N 112.7W 80 KT 90 MPH 120H 09/1200Z 27.3N 114.8W 60 KT 70 MPH $$ Forecaster Cangialosi