ZCZC MIATCDAT1 ALL TTAA00 KNHC DDHHMM Tropical Storm Nate Discussion Number 9 NWS National Hurricane Center Miami FL AL162017 1000 AM CDT Fri Oct 06 2017 Reports from Air Force Reserve and NOAA Hurricane Hunter aircraft indicate that Nate lacks an inner wind core at the present time, with the maximum winds located about 50 n mi from the center. The central pressure is fluctuating near 996 mb, and the aircraft- reported winds support an initial intensity of 45 kt. This is in good agreement with the satellite intensity estimates from TAFB and SAB. Satellite imagery shows that convection associated with Nate has been increasing during the past several hours, and that the storm has good outflow in the western semicircle. The center has moved generally northward during the past 12 hr. However, the latest recon fixes and satellite imagery suggest that a north-northwestward motion is resuming at about 18 kt. Nate is 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 36 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. While the guidance is in good agreement with this scenario, there has been a rightward shift to the latest guidance, likely due to the recent northward motion. The new forecast track is thus also shifted to the east of the previous forecast, and it now calls for the center of Nate to pass near or over the northeastern tip of the Yucatan Peninsula in about 12 h, followed by landfall on the northern Gulf Coast between 36-48 h. The new track is in the center of the guidance envelope in good agreement with the various consensus models. Conditions appear favorable for 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. It should be noted that the Rapid Intensification Index of the SHIPS model continues to indicate an above normal chance of rapid intensification. However, the current structure of the cyclone does not favor rapid development. KEY MESSAGES: 1. Nate could be near hurricane intensity when it approaches the Yucatan Peninsula later today 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 has been issued from Morgan City, Louisiana, to the Alabama/Florida border. Residents in these areas should heed any evacuation instructions given by local officials. 3. A hurricane warning has been has been issued 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 12 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 06/1500Z 18.7N 85.0W 45 KT 50 MPH 12H 07/0000Z 21.3N 86.3W 50 KT 60 MPH 24H 07/1200Z 24.8N 88.3W 60 KT 70 MPH 36H 08/0000Z 28.1N 89.3W 70 KT 80 MPH 48H 08/1200Z 31.1N 88.1W 60 KT 70 MPH...INLAND 72H 09/1200Z 37.5N 80.5W 30 KT 35 MPH...INLAND 96H 10/1200Z 42.0N 70.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 11/1200Z...DISSIPATED $$ Forecaster Beven NNNN