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| #1149102 (Received by flhurricane at: 10:57 AM 23.Aug.2023) TCDAT3 Tropical Storm Franklin Discussion Number 12 NWS National Hurricane Center Miami FL AL082023 1100 AM EDT Wed Aug 23 2023 Franklin`s center appears to have made landfall a little to the south of Barahona, Dominican Republic, shortly before 1200 UTC, and it is now moving northward over the mountainous terrain of the country. Heavy rains have likely overspread much of Hispaniola, although the deepest convection is occurring along the south-central coast of the island. It is assumed that the maximum winds have decreased now that the center is over land, and the initial intensity is set at 35 kt, which is close to the latest UW-CIMSS AiDT and D-PRINT estimates. Franklin`s speed has picked up a bit, and it is moving toward the north (005 degrees) at 11 kt. The storm continues to move northward through a break in the subtropical ridge, but it is expected to turn northeastward in the next 24-36 hours when it becomes positioned near the southern extent of a large mid-latitude trough over the western Atlantic. Then, in about 3 days, the central Atlantic ridge is expected to strengthen and block Franklin`s eastward progress, forcing the storm to turn toward the north by days 4 and 5. The track guidance is tightly clustered during the first 60-72 hours of the forecast, and the NHC track forecast is very close to the previous prediction and the various consensus aids. After 72 hours, the guidance suggests that the northward turn may be a little delayed. In response, the NHC track has been shifted a bit to the east of the previous forecast at days 4 and 5. Franklin will still be affected by moderate-to-strong west-southwesterly shear when it moves off the coast of Hispaniola later today, so it will likely take some time for the circulation to reorganize itself after moving over the rugged terrain. Otherwise, environmental conditions should support gradual strengthening starting in about 24 hours. In about 3 days, a developing upper-level low near the Bahamas is likely to provide a more favorable diffluent environment aloft over Franklin, potentially fostering more significant strengthening. Although there is a fairly wide range of intensity possibilities in the deterministic and ensemble intensity guidance on days 3-5, the overall guidance envelope has been trending higher. The NHC intensity forecast follows that tendency and is higher than the previous forecast on days 4 and 5. KEY MESSAGES: 1. Heavy rainfall from Franklin is expected across much of Hispaniola into Thursday, which is expected to produce significant and potentially life-threatening flash and urban flooding as well as mudslides, particularly over central Hispaniola. 2. Franklin is bringing tropical storm conditions to portions of the Dominican Republic and Haiti, where Tropical Storm Warnings are in effect, and tropical storm conditions are expected to begin within the Turks and Caicos Islands later today or tonight. FORECAST POSITIONS AND MAX WINDS INIT 23/1500Z 18.9N 70.9W 35 KT 40 MPH...OVER DOMINICAN REPUB. 12H 24/0000Z 20.5N 70.4W 35 KT 40 MPH...OVER WATER 24H 24/1200Z 22.1N 69.5W 40 KT 45 MPH 36H 25/0000Z 22.8N 68.2W 50 KT 60 MPH 48H 25/1200Z 23.1N 67.0W 55 KT 65 MPH 60H 26/0000Z 23.4N 66.0W 60 KT 70 MPH 72H 26/1200Z 24.3N 65.7W 65 KT 75 MPH 96H 27/1200Z 27.3N 66.7W 80 KT 90 MPH 120H 28/1200Z 31.1N 67.6W 90 KT 105 MPH $$ Forecaster Berg |
