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| #1017165 (Received by flhurricane at: 10:41 AM 16.Sep.2020) TCDAT4 Hurricane Sally Discussion Number 22 NWS National Hurricane Center Miami FL AL192020 1000 AM CDT Wed Sep 16 2020 NWS Doppler Radar and fixes from an Air Force Reserve Hurricane Hunter aircraft indicate that Sally made landfall near Gulf Shores, Alabama, around 0945 UTC with an intensity of 90 kt and a minimum central pressure of 965 mb. Since that time, the center has been inching its way inland over southeastern Alabama and the extreme western portion of the Florida panhandle. The eye has degraded in radar imagery, and Doppler velocities are gradually decreasing. The intensity has therefore been reduced to 70 kt for this advisory. Sally should continue to rapidly weaken today, and once the majority of the circulation is onshore by Thursday morning, it should weaken to a tropical depression. The remnant low is forecast to be absorbed by a frontal boundary near the southeastern United States coastline in a couple of days. Radar and the earlier aircraft fixes show that the longer-term motion is 030/4 kt. Sally should continue to move north- northeastward to northeastward with a gradual increase in forward speed as it enters the southern extent of the mid-latitude westerlies over the next 24-36 hours. A faster east-northeastward motion is expected by 36-48 hours before Sally or its remnants merge with the aforementioned frontal zone. The updated NHC track forecast is close to the HFIP corrected consensus, which is slightly north of the previous advisory. As Sally moves inland, ongoing heavy rainfall and flooding will spread northeastward across southeastern Alabama and portions of Georgia and western South Carolina during the next day or two. KEY MESSAGES: 1. Historic and catastrophic flooding, including widespread moderate to major river flooding, is unfolding along and just inland from west of Tallahassee, Florida, to Mobile Bay, Alabama. Significant and widespread flooding is likely across inland portions of Alabama into central Georgia, and possible across western South Carolina, western and central North Carolina, and far southeast Virginia. 2. Life-threatening storm surge is occurring along portions of the coastline from Alabama to the western Florida Panhandle, including Pensacola Bay. 3. Hurricane conditions are expected to continue this afternoon within portions of the Hurricane Warning area in southern Alabama and the western Florida panhandle. FORECAST POSITIONS AND MAX WINDS INIT 16/1500Z 30.6N 87.4W 70 KT 80 MPH...INLAND 12H 17/0000Z 31.3N 86.7W 45 KT 50 MPH...INLAND 24H 17/1200Z 32.4N 85.4W 30 KT 35 MPH...INLAND 36H 18/0000Z 33.6N 83.1W 25 KT 30 MPH...INLAND 48H 18/1200Z 34.6N 80.2W 25 KT 30 MPH...POST-TROP/REMNT LOW 60H 19/0000Z...DISSIPATED $$ Forecaster Brown |