ZCZC MIATCDEP4 ALL TTAA00 KNHC DDHHMM TROPICAL STORM DOUGLAS DISCUSSION NUMBER 16 NWS NATIONAL HURRICANE CENTER MIAMI FL EP042014 800 AM PDT WED JUL 02 2014 Douglas's structure has changed little since the last advisory. Deep convection associated with the storm is losing a bit of organization but remains compact near the low-level center. A blend of Dvorak final-T and CI numbers from TAFB, SAB, and the objective ADT supports maintaining an initial intensity of 40 kt. Douglas is trapped in an environment of weak steering and is drifting northwestward...or 325/2 kt...toward a break in the subtropical ridge. The subtropical high to the west of Douglas is expected to remain in place for another 48 hours or so, which will continue a slow northwestward motion. After 48 hours, the western subtropical high weakens while mid-level ridging strengthens over the western United States. This pattern evolution should cause Douglas to turn west-northwestward and accelerate between 72-120 hours. The track guidance has shifted noticeably to the right of the previous NHC forecast, especially through 24 hours and again between 96-120 hours. The updated forecast is also moved to the right, lying near the ECMWF and just to the left of the model consensus TVCE. Given Douglas's slow motion in the short term, sea surface temperatures will only gradually decrease along the forecast track during the next 24-36 hours. Vertical shear is forecast to remain low, and as a result, Douglas should be able to hang on as a tropical storm for another day or so. The ocean becomes much colder once Douglas accelerates to the west-northwest, and the cyclone is expected to become a remnant low by 48 hours. The new NHC intensity forecast is very similar to the previous one. FORECAST POSITIONS AND MAX WINDS INIT 02/1500Z 19.7N 116.0W 40 KT 45 MPH 12H 03/0000Z 20.0N 116.1W 35 KT 40 MPH 24H 03/1200Z 20.4N 116.4W 35 KT 40 MPH 36H 04/0000Z 20.9N 117.0W 30 KT 35 MPH 48H 04/1200Z 21.4N 118.0W 30 KT 35 MPH...POST-TROP/REMNT LOW 72H 05/1200Z 22.6N 120.8W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 06/1200Z 24.0N 124.0W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 07/1200Z 24.5N 127.5W 20 KT 25 MPH...POST-TROP/REMNT LOW $$ Forecaster Berg NNNN