000 WTPZ43 KNHC 172033 TCDEP3 Tropical Depression Eighteen-E Discussion Number 1 NWS National Hurricane Center Miami FL EP182019 200 PM PDT Thu Oct 17 2019 Conventional satellite imagery and a series of microwave overpasses indicate that the area of low pressure located about 1400 miles southwest of the southern tip of the Baja California peninsula has developed a well-defined center of circulation. The much improved cloud pattern consists of prominent convective curved bands in the east semicircle and recent bursts of deep convection with cold cloud tops of -70C near the center. Dvorak intensity estimates from both TAFB and SAB support an initial intensity of 30 kt, and advisories are being initiated on a tropical depression at this time. The intensity forecast is a bit hazy. However, all of the large- scale models and the statistical-dynamical intensity guidance show only slight intensification through the 72 hour period. The inhibiting contribution appears to be a rather dry low- to mid-level surrounding environment. Beyond 72 hours, most of the global and regional models show the cyclone weakening into a remnant low and remaining embedded in the Intertropical Convergence Zone (ITCZ). Consequently, the NHC forecast calls for only modest strengthening into a tropical storm in 12 hours, then weakening back to a depression in 36 hours. Through the remainder of the forecast, the cyclone should degenerate into a remnant low in 3 days or less, as the global guidance shows. The initial motion appears to be a rather unpredictable slow drift within weak low- to mid-level steering currents while attached to the ITCZ. The global models are unanimous in maintaining an erratic looping track pattern through the entire period, and the official forecast follows suit, based primarily on a blend of the GFS and ECMWF deterministic models. FORECAST POSITIONS AND MAX WINDS INIT 17/2100Z 10.1N 126.5W 30 KT 35 MPH 12H 18/0600Z 10.3N 126.8W 35 KT 40 MPH 24H 18/1800Z 10.8N 126.8W 35 KT 40 MPH 36H 19/0600Z 11.4N 126.4W 30 KT 35 MPH 48H 19/1800Z 11.6N 125.9W 30 KT 35 MPH 72H 20/1800Z 11.1N 125.7W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 21/1800Z 10.9N 125.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 22/1800Z 11.7N 124.9W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Roberts