000 WTPZ41 KNHC 202036 TCDEP1 TROPICAL DEPRESSION SIXTEEN-E DISCUSSION NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL EP162015 300 PM MDT SUN SEP 20 2015 Recent ASCAT data indicate that the low pressure area off the west coast of the Baja California peninsula has a low-level center located within a 30-45 nm wide area of light winds. This area is small enough to meet the criterion of a well-defined center, and the low is therefore being classified as a tropical depression. The ASCAT data and a recent ship report indicate that the intensity is 30 kt. The depression is located between a mid-level ridge centered over the northwestern Gulf of Mexico and a mid-/upper-level cut-off low located well west of the Baja California peninsula. This pattern is steering the depression quickly north-northwestward with an initial motion of 345/12 kt. The depression is expected to turn northward soon and continue that heading through 36 hours. The track guidance is tightly clustered, and the NHC official track forecast is very close to a consensus of the GFS and ECMWF. The depression will be moving across the Baja California peninsula by tonight, and southwesterly shear is expected to increase to near 25 kt in 12 hours and 35-40 kt by 24 hours. Therefore, strengthening is not expected, and the system should remain as a tropical depression while it moves across the Baja California peninsula and the Gulf of California. The associated deep convection is likely to be sheared away from the center by 36 hours, making the system a remnant low when it moves into southern Arizona. Dissipation is expected by 48 hours. Moisture associated with the depression is expected to cause heavy rainfall across portions of the Baja California peninsula, northwestern mainland Mexico, southern California, and Arizona during the next several days. These rains could cause life-threatening flash floods and mudslides, especially in areas of mountainous terrain. FORECAST POSITIONS AND MAX WINDS INIT 20/2100Z 25.0N 113.7W 30 KT 35 MPH 12H 21/0600Z 27.1N 113.5W 30 KT 35 MPH...INLAND 24H 21/1800Z 30.3N 112.8W 30 KT 35 MPH...OVER WATER 36H 22/0600Z 32.8N 112.3W 20 KT 25 MPH...POST-TROP/REMNT LOW 48H 22/1800Z...DISSIPATED $$ Forecaster Berg