000 WTNT45 KNHC 260849 TCDAT5 Tropical Storm Dorian Discussion Number 8 NWS National Hurricane Center Miami FL AL052019 500 AM AST Mon Aug 26 2019 Satellite images indicate that deep convection associated with Dorian continues to fluctuate curtailing significant strengthening likely due to intrusions of dry air. The overall trend, however, suggests that Dorian is gradually getting better organized with its cloud pattern consisting of a compact central dense overcast and some broken outer bands. The initial intensity is nudged up to 50 kt based on a blend of the satellite intensity estimates. Dorian remains a small storm with its tropical-storm-force winds estimated to extend no more than 40 n mi from the center. During the next couple of days, as Dorian moves through the Windward Islands and across the eastern Caribbean, slow strengthening seems likely due to low wind shear conditions and high SSTs. However, the surrounding dry air around the cyclone should continue to limit the rate of intensification. When Dorian approaches Hispaniola in about 3 days, the models show an increase in shear and those stronger environmental winds and the potential interaction with the rugged terrain of Hispaniola suggest that significant weakening is likely. The NHC intensity forecast remains between the dynamical models that show little or no strengthening and the statistical DSHP and LGEM that show significant intensification. It should be noted that the GFS and ECMWF have been very consistent in showing Dorian dissipating over the Caribbean Sea. Due to the wide range of the model solutions, the NHC intensity forecast remains of low confidence. It should be noted that compact tropical cyclones like Dorian are often challenging to predict. Dorian is moving westward at 12 kt steered by a subtropical ridge to its north. The storm should turn west-northwestward today and then northwestward on Wednesday when the cyclone gets closer to the eastern end of the mid- to upper-level low. The track models have shifted slightly to the right or north this cycle, and the NHC track forecast has been nudged in that direction. Key Messages: 1. Dorian is expected to bring tropical storm conditions to portions of the Lesser Antilles, where tropical storm watches and warnings are in effect. Residents in these areas should refer to advice from local government officials and products from their local meteorological service for additional information. 2. Dorian is expected to produce 2 to 4 inches of rain in Barbados, the Windward Islands, and Dominica, with isolated amounts as high as 6 inches. 3. While it is too soon to determine the specific time or magnitude of possible direct impacts in Puerto Rico, the Virgin Islands, or Hispaniola, interests in those areas should monitor the progress of Dorian and watches could be required later today. FORECAST POSITIONS AND MAX WINDS INIT 26/0900Z 11.9N 56.4W 50 KT 60 MPH 12H 26/1800Z 12.4N 58.2W 50 KT 60 MPH 24H 27/0600Z 13.2N 60.3W 55 KT 65 MPH 36H 27/1800Z 14.4N 62.4W 55 KT 65 MPH 48H 28/0600Z 15.5N 64.5W 60 KT 70 MPH 72H 29/0600Z 18.0N 68.4W 65 KT 75 MPH 96H 30/0600Z 20.8N 71.6W 30 KT 35 MPH 120H 31/0600Z 23.0N 75.0W 30 KT 35 MPH $$ Forecaster Cangialosi