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| #1148646 (Received by flhurricane at: 11:03 PM 20.Aug.2023) TCDAT3 Tropical Storm Franklin Discussion Number 2 NWS National Hurricane Center Miami FL AL082023 1100 PM AST Sun Aug 20 2023 Deep convection continues to burst near and to the east of the center of Franklin. Earlier NOAA aircraft fixes and more recent microwave satellite data indicate that the center of Franklin is located near the northwestern edge of the deep convection due to moderate westerly shear. The latest Dvorak T-number from TAFB is T3.0 (45 kt) and SAB provided a data T-number of T2.5 (35 kt). A very recently arriving ASCAT pass revealed peak winds of 40-45 kt, therefore the initial intensity has been raised to 45 kt. Franklin is moving west-northwestward at about 11 kt. A slower westward to west-northwest motion is forecast overnight. By late Monday, a deepening trough over the western Atlantic is forecast to cause Franklin to turn northwestward and then northward toward Hispaniola. The tropical storm is forecast to pass over that island Tuesday night, and then move off the north coast of Hispaniola by early Wednesday. After that time, the amplifying trough is forecast to turn Franklin northeastward. There is still a fair amount of spread on where the northward turn will take place and the official forecast remains near the middle of the guidance envelope. Franklin is expected to remain in an environment of moderate westerly shear during the next couple of days, but it is not likely to prevent some modest strengthening before Franklin reaches the southern coast of Hispaniola. Interaction with the mountainous terrain of Hispaniola is expected to cause some weakening. Once Franklin moves into the western Atlantic, most of the intensity guidance suggests additional strengthening is likely and the NHC forecast follows suit. The NHC intensity forecast is a blend of the HFIP corrected consensus model and the IVCN multi-model consensus aid. Based on the current track forecast, a tropical storm warning has been issued for the entire southern coastline of Haiti and the Dominican Republic. KEY MESSAGES: 1. Heavy rainfall from Franklin is expected across portions of Puerto Rico and Hispaniola through the middle of the week. The heavy rainfall may produce areas of flash and urban flooding as well as river rises and mudslides. Across Hispaniola, significant and potentially life-threatening flash flooding is possible Tuesday into Wednesday. 2. Franklin is expected to bring tropical storm conditions to portions of the Dominican Republic and Haiti beginning on Tuesday where Tropical Storm Warnings are in effect. FORECAST POSITIONS AND MAX WINDS INIT 21/0300Z 14.9N 68.3W 45 KT 50 MPH 12H 21/1200Z 15.0N 70.0W 50 KT 60 MPH 24H 22/0000Z 15.3N 71.0W 50 KT 60 MPH 36H 22/1200Z 16.2N 71.5W 55 KT 65 MPH 48H 23/0000Z 18.1N 71.4W 55 KT 65 MPH...INLAND 60H 23/1200Z 20.0N 70.9W 45 KT 50 MPH...OVER WATER 72H 24/0000Z 21.9N 69.9W 50 KT 60 MPH 96H 25/0000Z 24.3N 67.0W 60 KT 70 MPH 120H 26/0000Z 26.2N 64.4W 70 KT 80 MPH $$ Forecaster Brown |
