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| #1149066 (Received by flhurricane at: 5:05 AM 23.Aug.2023) TCDAT3 Tropical Storm Franklin Discussion Number 11 NWS National Hurricane Center Miami FL AL082023 500 AM EDT Wed Aug 23 2023 Franklin`s cloud pattern continues to become gradually better organized with a large convective band evident over the eastern semicircle of the circulation. There is still some westerly shear over the system, and most of the deep convection is confined to the northeast and southeast quadrants of the storm. Franklin appears to be producing high-level anticyclonic outflow which is being undercut by westerlies just below the outflow level. Subjective Dvorak intensity estimates range from 35 to 45 kt, and most of the objective estimates are in this range as well. A scatterometer overpass from several hours ago indicated maximum winds near 40 kt. The current intensity is set at 45 kt. Although the center remains difficult to locate, satellite center fixes from TAFB and SAB and continuity suggest a motion of about 010/9 kt. Franklin is moving through a weakness in the mid-level subtropical ridge. During the next couple of days, the cyclone is forecast to turn toward the east-northeast and move along the northwestern side of a mid-level anticyclone, and south of a higher-latitude trough. In 3 to 5 days, as the trough lifts out and a mid-level ridge to the west and northwest of Franklin builds slightly, the system is expected to turn northward and north-northwestward. The official track forecast is again close to the HCCA consensus and very similar to the previous advisory`s prediction. Land interaction with the mountains of Hispaniola today are likely to disrupt Franklin`s circulation, and the amount of weakening shown by the NHC short-term intensity forecast may be conservative. After the cyclone moves over the Atlantic, strengthening is anticipated. However, the global models show significant shear associated with an upper-level cyclone over the southwestern Atlantic near 70W in 3-5 days, and this is also indicated in the SHIPS guidance. Because of this, the official intensity forecast is near the low end of the model guidance and similar to the LGEM prediction. This is just slightly higher than the previous official forecast. KEY MESSAGES: 1. Heavy rainfall from Franklin is expected across much of Hispaniola into Thursday. The heavy rainfall is expected to produce significant and potentially life-threatening flash and urban flooding as well as mudslides, particularly over central Hispaniola today. 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 23/0900Z 17.4N 71.3W 45 KT 50 MPH 12H 23/1800Z 19.0N 71.0W 35 KT 40 MPH...INLAND 24H 24/0600Z 21.1N 70.5W 35 KT 40 MPH 36H 24/1800Z 22.2N 69.3W 45 KT 50 MPH 48H 25/0600Z 22.7N 68.1W 55 KT 65 MPH 60H 25/1800Z 23.0N 67.0W 60 KT 70 MPH 72H 26/0600Z 23.3N 66.4W 65 KT 75 MPH 96H 27/0600Z 25.8N 66.8W 75 KT 85 MPH 120H 28/0600Z 29.5N 68.0W 80 KT 90 MPH $$ Forecaster Pasch |
