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| #1149907 (Received by flhurricane at: 4:39 PM 28.Aug.2023) TCDAT3 Hurricane Franklin Discussion Number 33 NWS National Hurricane Center Miami FL AL082023 500 PM EDT Mon Aug 28 2023 Visible and infrared satellite imagery depicts Franklin remains a powerful major hurricane this afternoon. The eye has cleared out and warmed, with a thick symmetric eyewall tightly wrapped around the center. Subjective and objective satellite estimates have remained fairly steady throughout the day, around T6.5. Given that the satellite appearance remains similar to earlier today when we had aircraft reconnaissance data, the intensity remains at 125 kt for this advisory. Air Force Reserve Hurricane Hunters will be investigating the system later this evening. Franklin is moving northward at 350/8 kt. A northward then northeastward motion is forecast during the next 48 hours as Franklin rounds the western edge of the subtropical ridge. In a couple of days, a deep trough is expected to move off the northeast coast of the U.S. and eastern Canada, with Franklin becoming captured in the southwesterly flow, causing an increase in forward motion to the northeast. The model guidance for this cycle remained in fairly good agreement except for the ECMWF, which shifted back to the right. There is still a difference in the a long track guidance, with the GFS being on the faster side of the model envelope. The NHC track forecast is fairly similar to the previous, and lies near the corrected consensus aids. Some additional intensification is possible as Franklin remains over warm sea-surface temperatures and low vertical wind shear. The latest peak intensity is unchanged from the previous forecast, bringing Franklin to a strong Category 4 hurricane. The short term forecast is subject to fluctuations in inner core changes, or eyewall replacement cycles, which could occur at any time, making the peak intensity forecast a little more challenging. Some gradual weakening is forecast in about 24 hours as models indicate a increase in northwesterly shear. Toward the end of the forecast period, further weakening is expected as Franklin encounters increased vertical wind shear and moves over cooler SSTs. Models are in fairly good agreement with the system becoming an extratropical cyclone around 96 h, and the forecast now explicitly shows this transition occuring in 96 h. KEY MESSAGES: 1.Tropical storm conditions are possible on Bermuda beginning Wednesday morning, when Franklin is forecast to make its closest approach to the island. 2. Life-threatening surf and rip currents are occurring along the coast of the southeast United States. These conditions are expected to spread northward along the remainder of the U.S. east coast, Atlantic Canada, and Bermuda during the next couple of days. FORECAST POSITIONS AND MAX WINDS INIT 28/2100Z 28.5N 71.0W 125 KT 145 MPH 12H 29/0600Z 29.7N 71.1W 135 KT 155 MPH 24H 29/1800Z 31.3N 70.3W 130 KT 150 MPH 36H 30/0600Z 33.0N 68.8W 120 KT 140 MPH 48H 30/1800Z 34.9N 66.3W 110 KT 125 MPH 60H 31/0600Z 37.2N 62.0W 100 KT 115 MPH 72H 31/1800Z 39.6N 57.3W 90 KT 105 MPH 96H 01/1800Z 45.6N 48.3W 75 KT 85 MPH...POST-TROP/EXTRATROP 120H 02/1800Z 50.4N 37.6W 60 KT 70 MPH...POST-TROP/EXTRATROP $$ Forecaster Kelly/Brown |
