000 WTPZ41 KNHC 290240 TCDEP1 Tropical Depression Sixteen-E Discussion Number 1 NWS National Hurricane Center Miami FL EP162022 1000 PM CDT Wed Sep 28 2022 The area of low pressure located south of the southwestern coast of Mexico has steadily gained organization throughout the day. Recent microwave imagery indicated the formation of convective banding and an earlier partial ASCAT pass suggested the system likely has a well-defined center. Recent Dvorak classifications from TAFB and SAB were both 2.0, another sign that the system has become better organized. Collectively these data support classifying the system as a tropical cyclone, and advisories have been initiated on Tropical Depression Sixteen. For the next 48 to 60 h, the forecast is fairly straightforward with high confidence. The depression is moving toward the west-northwest near 9 kt, and that general motion should continue as the system is steered by a mid-level ridge centered over Mexico. Environmental conditions appear conducive for strengthening, and all of the intensity models suggest it will become a tropical storm quickly, and continue strengthening to hurricane intensity a day or two after that. The main concern with the forecast is what happens beyond 60 h, when confidence in the forecast decreases considerably. There is a clear bifurcation in the track guidance at that point that appears to be linked to the intensity and vertical extent of the cyclone. If the cyclone is relatively deep at that point, which is shown by all of the normally reliable intensity guidance, it will likely turn northward or north-northeastward as it interacts with a mid- to upper-level trough. However, some models like the ECMWF forecast a shallower cyclone that takes a drastically different path slowly westward, steered primarily by lower-level winds. The result is a massive spread in the track guidance, with most of the consensus aids caught somewhat between those two scenarios. Although the ECMWF solution can not be dismissed entirely, the more skillful intensity guidance (supported by the favorable environment) suggest that the eastern solution toward Mexico may be more likely. The NHC forecast therefore favors the northeastern solution and shows the cyclone moving toward the coast of Mexico by 72-96 h. Strong upper-level winds associated with the aforementioned trough and a drier surrounding environment should cause the cyclone to weaken as it moves closer to the coast, and it will likely quickly dissipate if it moves inland. The NHC intensity forecast is close to the intensity consensus throughout the forecast, except at 96 h to reflect that the official forecast position is still over water at that time. FORECAST POSITIONS AND MAX WINDS INIT 29/0300Z 14.4N 103.7W 30 KT 35 MPH 12H 29/1200Z 15.1N 105.3W 35 KT 40 MPH 24H 30/0000Z 16.1N 107.1W 45 KT 50 MPH 36H 30/1200Z 16.8N 108.3W 55 KT 65 MPH 48H 01/0000Z 17.5N 108.5W 65 KT 75 MPH 60H 01/1200Z 18.5N 108.1W 70 KT 80 MPH 72H 02/0000Z 19.7N 107.7W 75 KT 85 MPH 96H 03/0000Z 23.0N 107.0W 60 KT 70 MPH 120H 04/0000Z 25.0N 106.0W 25 KT 30 MPH...POST-TROP/INLAND $$ Forecaster D. Zelinsky