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#905979 (Received by flhurricane at: 5:10 PM 06.Oct.2017) TCDAT1 Tropical Storm Nate Discussion Number 10...Corrected NWS National Hurricane Center Miami FL AL162017 400 PM CDT Fri Oct 06 2017 CORRECTED MAX RAINFALL AMOUNT IN KEY MESSAGES Satellite imagery this afternoon indicates that convection associated with Nate is becoming better organized, with a strong convective band now wrapping about three-quarters of the way around the center. Recent data from NOAA buoy 42056 near the center suggest the central pressure has fallen to near 993 mb, and the buoy just reported a 1-minute average wind of 49 kt. Based on this, the initial intensity is increased to a possibly conservative 50 kt. The next aircraft investigating Nate is scheduled to arrive near 22Z. The initial motion is north-northwestward or 340/18 kt. Nate remains between a complex deep-layer low pressure area over the western Gulf of Mexico and Central America and a building ridge of high pressure over the western Atlantic. This combination should steer the storm quickly north-northwestward for the next 24 h or so. After that, Nate should turn northward and northeastward as it goes around the western edge of the ridge and recurves into the mid-latitude westerlies. The guidance remains in good agreement with the direction of motion, and it has come into better agreement on the speed. Thus, the new forecast track is similar to, but slightly to the west of the the previous track, and it calls for the center of Nate to pass near or over the northeastern tip of the Yucatan Peninsula in about 6 h, followed by landfall on the northern Gulf Coast around the 36-h point. It should be noted that the ECMWF and GFS are both a little to the left of the current track. Conditions appear favorable for continued strengthening up to landfall on the northern Gulf Coast, and Nate is expected to make landfall there as a hurricane. The new intensity forecast, which is an update of the previous one, lies near the upper edge of the intensity guidance. Given the current developments, there is still a possibility of a period of rapid intensification as Nate crosses the Gulf of Mexico. As alternative scenarios to the actual forecast of steady strengthening, the ECMWF forecasts no additional strengthening as Nate crosses the Gulf of Mexico, and the GFS/UKMET forecast little additional strengthening until the last 12 h before landfall. KEY MESSAGES: 1. Nate could be near hurricane intensity when it passes near or over the Yucatan Peninsula during the next several hours bringing direct impacts from wind, storm surge, and heavy rainfall. A tropical storm warning and a hurricane watch are in effect for a portion of this area, and life-threatening flash flooding is also possible. 2. Life-threatening storm surge flooding is likely along portions of the northern Gulf Coast, and a storm surge warning is now in effect from Morgan City, Louisiana, to the Okaloosa/Walton county line in Florida. Residents in these areas should heed any evacuation instructions given by local officials. 3. A hurricane warning is in effect for portions of the northern Gulf Coast from Louisiana to Alabama, and preparations to protect life and property should be rushed to completion in these areas. 4. Nate will bring heavy rainfall of 3 to 6 inches with isolated totals of 10 inches from the central Gulf Coast states into the eastern Tennessee Valley and southern Appalachians through this weekend, resulting in the possibility of flash flooding in these areas. 5. Heavy rainfall from Nate will continue to be a threat in portions of Central America, with life-threatening flash flooding and mud slides possible in portions of Nicaragua, Honduras, Costa Rica, Panama, and Belize through tonight. FORECAST POSITIONS AND MAX WINDS INIT 06/2100Z 20.3N 85.7W 50 KT 60 MPH 12H 07/0600Z 23.0N 87.2W 55 KT 65 MPH 24H 07/1800Z 26.8N 88.9W 60 KT 70 MPH 36H 08/0600Z 29.9N 89.1W 70 KT 80 MPH 48H 08/1800Z 33.1N 87.2W 45 KT 50 MPH...INLAND 72H 09/1800Z 39.5N 78.5W 25 KT 30 MPH...INLAND 96H 10/1800Z 43.5N 66.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 11/1800Z...DISSIPATED $$ Forecaster Beven |