000 WTNT42 KNHC 051445 TCDAT2 TROPICAL DEPRESSION SEVEN DISCUSSION NUMBER 1 NWS NATIONAL HURRICANE CENTER MIAMI FL AL072015 1100 AM AST SAT SEP 05 2015 Satellite imagery and ship observations indicate that the disturbance south of the Cape Verde Islands has become better organized, and is now Tropical Depression Seven. The convection is not very deep at this time, but animation of visible images show a good circulation. In fact, earlier microwave data clearly depict a mid-level center associated with the developing depression. Based on Dvorak estimates from TAFB and SAB of 2.0 and 2.5, respectively, the initial intensity has been set at 30 kt. No ASCAT data were available at the time of this advisory. The environment appears to be favorable for gradual strengthening during the next 2 to 3 days. After that time, most of the global models forecast a significant increase in shear. This should halt any additional strengthening, and most likely the cyclone will weaken or could even dissipate well east of the Lesser Antilles. The best estimate of the initial motion is toward the west or 280 degrees at 12 kt. A moderately strong subtropical ridge is centered north of the depression. This pattern calls for a continuation of a general westward track for the next 3 days. After that time, the ridge is expected to weaken, and the cyclone will likely turn more toward the west-northwest with a decrease in forward speed. This is the solution of the models, except the ECMWF that does not acknowledge the existence of a cyclone. FORECAST POSITIONS AND MAX WINDS INIT 05/1500Z 12.3N 25.2W 30 KT 35 MPH 12H 06/0000Z 12.5N 26.9W 30 KT 35 MPH 24H 06/1200Z 12.8N 29.2W 35 KT 40 MPH 36H 07/0000Z 13.0N 32.0W 40 KT 45 MPH 48H 07/1200Z 13.5N 34.7W 45 KT 50 MPH 72H 08/1200Z 14.5N 40.0W 50 KT 60 MPH 96H 09/1200Z 15.0N 45.5W 45 KT 50 MPH 120H 10/1200Z 15.5N 50.0W 40 KT 45 MPH $$ Forecaster Avila