ZCZC MIATCDEP4 ALL TTAA00 KNHC DDHHMM TROPICAL STORM DOUGLAS DISCUSSION NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL EP042014 800 PM PDT MON JUN 30 2014 Tropical Storm Douglas has developed some well-defined inner core banding features this evening, as seen in the GOES-West geostationary imagery. Correspondingly, the intensity estimates have inched upward: a blend of the TAFB and SAB Dvorak classifications averages 40 kt, the Advanced Dvorak Technique is at 43 kt, and the CIMSS AMSU technique suggests 48 kt. The initial intensity is thus set at 40 kt, but this could be slightly low. It appears that Douglas may soon be at its peak intensity, as the sea surface temperatures and convective instability start dropping steadily in about a day despite rather low vertical wind shear. The intensity guidance is tightly clustered and suggests gradual weakening after 24 h until loss of deep convection in about 3-4 days causes the system to become a remnant low. The intensity forecast is slightly above the previous advisory, mainly due to the short-term intensity trend. Douglas is moving west-northwestward at about 8 kt. The system is primarily being steered by a broad ridge to its north, which should weaken within the next day or so as a short-wave trough approaches from the west. When this occurs, the steering flow becomes almost negligible and Douglas is likely to drift slowly west-northwestward between 24 and 72 h. By days 4 and 5, the remnant low of Douglas will accelerate westward in the low-level tradewind flow. The track forecast is based upon TVCE - the variable consensus model - and is slightly north of the previous advisory. FORECAST POSITIONS AND MAX WINDS INIT 01/0300Z 18.4N 114.9W 40 KT 45 MPH 12H 01/1200Z 19.0N 115.5W 45 KT 50 MPH 24H 02/0000Z 19.4N 116.1W 45 KT 50 MPH 36H 02/1200Z 19.6N 116.5W 40 KT 45 MPH 48H 03/0000Z 19.7N 116.8W 35 KT 40 MPH 72H 04/0000Z 20.0N 118.0W 30 KT 35 MPH 96H 05/0000Z 20.5N 120.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 06/0000Z 21.0N 123.0W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ Forecaster Landsea NNNN