ZCZC MIATCDAT3 ALL TTAA00 KNHC DDHHMM Potential Tropical Cyclone Three Discussion Number 4 NWS National Hurricane Center Miami FL AL032017 1000 AM CDT Tue Jun 20 2017 Visible satellite imagery and surface observations indicate that the circulation of the low has become better organized since yesterday, but still lacks a well-defined center. The central pressure appears to have fallen to around 999 mb based on observations from NOAA buoy 42001, and some deep convection has begun developing a little closer to the low's circulation center. For now the system is being maintained as a potential tropical cyclone, however, the system could be classified as a tropical or subtropical cyclone later today. The current intensity is maintained at 35 kt based largely on continuity pending an Air Force Reserve Hurricane Hunter mission into the system later this morning. Only limited strengthening is forecast before the system moves inland due to the strong vertical shear over the cyclone caused by an upper-level low centered off the Texas coast. The new NHC intensity forecast is similar to the previous one and is close to the intensity consensus aid. The initial motion estimate is a somewhat uncertain 320/09 as the there are still multiple low-level cloud swirls circulating around a mean center, and some erratic motion is still possible until a better-defined center forms. However, the system should be steered generally northwestward over the next 36 hours or so as it interacts with the aforementioned upper-level low and then turns more north-northwestward by 48 hours as the system begins to recurve around the mid-level ridge to the east. The NHC track forecast is a little faster than the previous one in the short range, and shows the system moving inland over western Louisiana and eastern Texas by 48 hours. After that time, the system should recurve into the mid-latitude flow and accelerate northward and northeastward across the lower Mississippi Valley and into the southern and central Appalachians on days 3 and 4 before dissipating. The primary hazard from this disturbance is expected to be heavy rainfall over portions of the central and eastern Gulf Coast. Given the nature of the circulation and the fact that wind and rain hazards extend well north and east of the center, users are encouraged not to focus on the details of the track forecast. FORECAST POSITIONS AND MAX WINDS INIT 20/1500Z 25.9N 90.5W 35 KT 40 MPH...POTENTIAL TROP CYCLONE 12H 21/0000Z 26.7N 91.6W 40 KT 45 MPH...TROPICAL CYCLONE 24H 21/1200Z 27.4N 92.6W 40 KT 45 MPH 36H 22/0000Z 28.6N 93.6W 40 KT 45 MPH 48H 22/1200Z 30.1N 94.0W 35 KT 40 MPH...INLAND 72H 23/1200Z 34.0N 92.5W 25 KT 30 MPH...INLAND 96H 24/1200Z 37.5N 84.0W 20 KT 25 MPH...POST-TROP/INLAND 120H 25/1200Z...DISSIPATED $$ Forecaster Brennan NNNN