ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM TROPICAL DEPRESSION TWENTY-E DISCUSSION NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL EP202016 400 AM CDT SUN OCT 23 2016 Conventional and microwave satellite data indicate that deep convection associated with the low pressure area located south of Mexico has become much better organized overnight. A fortuitous 0526 UTC GPM microwave overpass revealed a significant increase in banding and was also very helpful in determining the center location. Based on these data, and an earlier partial ASCAT pass which indicated that the circulation had become sufficiently well defined, advisories are being initiated on the twentieth tropical depression of the 2016 eastern North Pacific hurricane season. The initial intensity has been set at 30 kt, which is in agreement with Dvorak T-numbers of 2.0 from both TAFB and SAB. The depression is forecast to move over SSTs of 29-30 degrees Celsius and remain in an area of vertical shear of around 10 kt or less during the next 2 to 3 days, which should allow for steady strengthening. Despite these seemingly favorable conditions, the global and regional hurricane models show much less strengthening than the statistical SHIPS/LGEM guidance which show a peak intensity of around 70-75 kt in about 3 days. Given the expected favorable conditions, the NHC intensity forecast is above the dynamical guidance and model consensus, but is lower than the SHIPS and LGEM. Late in the forecast period, cooler SSTs and increasing southwesterly vertical wind shear are expected to weaken the cyclone. Since the depression is still in the formative stage, the initial motion is a somewhat uncertain 290/14. A strong mid- to upper- level ridge that is forecast to shift westward over the Baja California peninsula should steer the cyclone west-northwestward during the next several days. By day 4, the cyclone is forecast to turn northwestward when it approaches the western periphery of the ridge. The track guidance is in good agreement on this overall scenario, but there are some differences in the forward speed of the cyclone and exactly when the northwestward turn will materialize. The NHC forecast track is slightly faster than the model consensus and is in best agreement with the latest ECMWF model. FORECAST POSITIONS AND MAX WINDS INIT 23/0900Z 13.1N 103.6W 30 KT 35 MPH 12H 23/1800Z 13.8N 105.6W 40 KT 45 MPH 24H 24/0600Z 14.7N 107.8W 45 KT 50 MPH 36H 24/1800Z 15.4N 110.2W 55 KT 65 MPH 48H 25/0600Z 16.1N 112.6W 65 KT 75 MPH 72H 26/0600Z 17.0N 117.1W 65 KT 75 MPH 96H 27/0600Z 18.8N 120.5W 55 KT 65 MPH 120H 28/0600Z 20.5N 122.5W 45 KT 50 MPH $$ Forecaster Brown NNNN