|
Show Selection: |
| #902551 (Received by flhurricane at: 10:53 PM 10.Sep.2017) TCDAT1 Hurricane Irma Discussion Number 48 NWS National Hurricane Center Miami FL AL112017 1100 PM EDT Sun Sep 10 2017 Irma`s center has moved northward across the western Florida peninsula since it made landfall earlier this afternoon, and it is now located over west-central Florida. NOAA WSR-88D radar data from Tampa Bay are showing 95-100 kt winds at an elevation of about 3500 ft, so the hurricane`s intensity is estimated to be 85 kt. Irma continues to have a large wind field, and exceptional hurricane- force wind gusts are still occurring well to the east of the center along the Florida east coast. Irma appears to be making some progress to the west of due north, and the longer-term initial motion is 350/12 kt. The cyclone is expected to swing around the eastern side of a mid-level disturbance currently located along the U.S. Gulf Coast, which should impart a north-northwestward to northwestward motion during the next 48 hours. Due to its recent more inland push, Irma`s center is now forecast to remain over Florida and then move over the southeastern United States for the duration of its existence. Due to continued land interaction and strong shear of over 30 kt, Irma should continue to lose strength and fall below hurricane intensity on Monday. The cyclone is then expected to become a remnant low over western Tennessee by day 3 and dissipate by day 4. KEY MESSAGES: 1. There is the danger of life-threatening storm surge flooding along much of the Florida coast, including the Florida Keys, and portions of the coasts of Georgia and South Carolina, where a Storm Surge Warning remains in effect. 2. Irma will continue to bring life-threatening wind impacts to much of Florida, with hurricane-force winds near the center. Also, Irma is a large hurricane, and hurricane-force wind gusts and sustained tropical-storm force winds extend far from the center. Wind hazards from Irma will also spread northward through Georgia and into portions of Alabama, Tennessee, South Carolina, and North Carolina. 3. Irma continues to produce very heavy rain and inland flooding across much of Florida, and these rains will spread into the rest of the southeast United States. Intense rainfall rates of 2 to 4 inches per hour is leading to flash flooding and rapid rises on creeks, streams, and rivers. Significant river flooding is likely over the next five days in the Florida peninsula and southern Georgia, where average rainfall totals of 8 to 15 inches and isolated 20 inch amounts are expected. Significant river flooding is possible beginning Monday and Tuesday in much of eastern and central Georgia, western South Carolina, and western North Carolina, where average rainfall of 3 to 8 inches and isolated 12 inch amounts are expected. The southern Appalachian Mountains will be especially vulnerable to flash flooding. Irma is also expected to produce average amounts of 2 to 5 inches in parts of Mississippi, Alabama and Tennessee, where isolated higher amounts and local flooding may occur. FORECAST POSITIONS AND MAX WINDS INIT 11/0300Z 27.5N 81.9W 85 KT 100 MPH...INLAND 12H 11/1200Z 29.4N 82.8W 65 KT 75 MPH...INLAND 24H 12/0000Z 31.9N 84.7W 45 KT 50 MPH...INLAND 36H 12/1200Z 33.9N 86.8W 30 KT 35 MPH...INLAND 48H 13/0000Z 35.0N 88.6W 25 KT 30 MPH...INLAND 72H 14/0000Z 37.5N 87.8W 20 KT 25 MPH...POST-TROP/INLAND 96H 15/0000Z...DISSIPATED $$ Forecaster Berg |
