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#938592 (Received by flhurricane at: 11:08 PM 04.Sep.2018) TCDAT2 Tropical Storm Gordon Discussion Number 11 NWS National Hurricane Center Miami FL AL072018 1000 PM CDT Tue Sep 04 2018 Aircraft and radar imagery shows that the center of Gordon is making landfall just west of the Alabama-Mississippi border. The radar imagery has shown an increase in convection around the center within the past couple of hours, and Doppler velocities have increased to 65-75 kt at about 2500 feet. A NOAA Hurricane Hunter aircraft has measured peak 700-mb flight-level winds of 63 kt. These data support an initial intensity of 60 kt. A NOAA Coastal Marine Observing site on Dauphin Island, Alabama has recently reported sustained winds of 49 kt with a gust to 63 kt. Once the center moves inland, Gordon should rapidly weaken and it is forecast to become a tropical depression on Wednesday morning. Gordon moved a little right of the previous forecast track this evening, but the most recent aircraft fixes suggest the center has jogged back toward the left. The longer-term motion estimate is 315/12 kt. A large deep-layer ridge located over the eastern United States is forecast to steer Gordon northwestward at a slower forward speed during the next couple of days. After that time, the cyclone should turn northward, then northeastward around the western periphery of the ridge. The updated NHC track is again close to a blend of the various consensus aids, but is a little right of previous forecast for the first 24-36 hours, primarily due to the slightly more eastward initial position. Key Messages: 1. Gordon is expected to bring life-threatening storm surge and hurricane conditions to portions of the central Gulf Coast, where a Storm Surge Warning and Hurricane Warning are in effect. The highest storm surge is expected along the coasts of Mississippi and Alabama from Biloxi to Dauphin Island tonight and early Wednesday. Tropical storm conditions and storm surge will also affect portions of the western Florida Panhandle. 2. Heavy rainfall from Gordon will affect the western Florida Panhandle, southwest Alabama, southern and central Mississippi, northeastern Louisiana, and southern Arkansas, where totals could reach as high as 12 inches. This rainfall will cause flash flooding in portions of these areas. FORECAST POSITIONS AND MAX WINDS INIT 05/0300Z 30.3N 88.4W 60 KT 70 MPH 12H 05/1200Z 31.5N 89.6W 35 KT 40 MPH...INLAND 24H 06/0000Z 32.7N 90.9W 25 KT 30 MPH...INLAND 36H 06/1200Z 33.5N 92.0W 25 KT 30 MPH...INLAND 48H 07/0000Z 34.3N 92.9W 20 KT 25 MPH...POST-TROP/REMNT LOW 72H 08/0000Z 36.0N 93.9W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 09/0000Z 38.3N 92.0W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 10/0000Z 41.0N 88.5W 20 KT 25 MPH...POST-TROP/EXTRATROP $$ Forecaster Brown |