000 WTPZ43 KNHC 250833 TCDEP3 TROPICAL STORM LESTER DISCUSSION NUMBER 3 NWS NATIONAL HURRICANE CENTER MIAMI FL EP132016 300 AM MDT THU AUG 25 2016 The cyclone appears to be gradually gaining strength. Recent microwave images show that the circulation of the system has become better organized with the associated banding features more tightly coiled than they were earlier. In addition, infrared satellite pictures indicate that a central dense overcast feature has formed with cloud tops colder than -70 deg C. The Dvorak classifications from TAFB and SAB are both 2.5/35 kt, and ADT values from CIMSS at the University of Wisconsin are a bit higher. Based on these data, the initial wind speed is increased to 35 kt, making the cyclone Tropical Storm Lester. The tropical cyclone is expected to steadily strengthen during the next 3 to 4 days while it remains over warm water, in a moist environment, and in moderate wind shear conditions. By the end of the forecast period, slight weakening should commence when Lester moves over cooler water and into a more stable air mass. The intensity guidance is a little higher this cycle, and the NHC forecast is nudged upward to be in closer agreement with the intensity model consensus. The microwave passes have been helpful in locating the center, and suggest that Lester is still moving west-northwestward at 10 kt. A decrease in forward speed is expected to begin later today when the cyclone moves closer to a break in the subtropical ridge. The ridge is expected to rebuild to the north of the storm this weekend, and that should cause Lester to move westward at a faster pace. The NHC track forecast is largely an update of the previous one, and it lies close to the consensus aids. FORECAST POSITIONS AND MAX WINDS INIT 25/0900Z 16.2N 111.6W 35 KT 40 MPH 12H 25/1800Z 16.7N 113.0W 45 KT 50 MPH 24H 26/0600Z 17.2N 114.4W 55 KT 65 MPH 36H 26/1800Z 17.5N 115.8W 60 KT 70 MPH 48H 27/0600Z 17.6N 117.3W 65 KT 75 MPH 72H 28/0600Z 17.7N 121.0W 75 KT 85 MPH 96H 29/0600Z 17.9N 125.8W 80 KT 90 MPH 120H 30/0600Z 18.0N 130.4W 75 KT 85 MPH $$ Forecaster Cangialosi