669 FXUS64 KHUN 092351 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 651 PM CDT Tue Oct 9 2018 .UPDATE... For 00Z TAFS. && .SYNOPSIS... Issued at 405 PM CDT Tue Oct 9 2018 High latitude upper level blocking was reforming over the Arctic and Bering Sea region of far NE Asia, and another more mid latitude one across the European/Asia border region. This was keeping a troughing setup over the western North American domain, which was partially being held in place by upper ridging off of the east coast. Adding to the mix is the development of Hurricane Michael, now moving northward over the eastern Gulf of Mexico around 500 miles south of Panama City. && .NEAR TERM...(Tonight) Issued at 405 PM CDT Tue Oct 9 2018 Michael is unfortunately expected to strengthen into a "major" hurricane in intensity (sustained winds greater than 120 mph) as it heads closer to shore. The 1 PM intermediate advisory had it making landfall in the Panama City area sometime tomorrow afternoon. Its current path should keep it and most effects well to the south of the Tennessee Valley. The tropical system as it moves to the southern Mid Atlantic region will in part help weaken the eastern trough, with the upper flow over the eastern CONUS becoming more zonal. Lower level moisture preceding Michael will continue to produce a cloudy trend across the forecast area tonight, bringing a slight chance of showers during the late and overnight. Tonight will be a last very warm night, with lows in the lower 70s. This may be the last unseasonably warm night for a while, if not the season, as noticeably colder air will follow over the next few days. .SHORT TERM...(Wednesday through Thursday) Issued at 405 PM CDT Tue Oct 9 2018 The weakening of the eastern ridge will allow a cold front currently positioned from the southern Great Lakes to the southern plains to move eastward. This front should make a move across the Tennessee Valley during Thursday. Lower level moisture pooling ahead of the front will bring scattered to numerous showers and thunderstorms to the region. Overall storm strength at this time does not look particularly strong or severe, but gusty winds and heavy downpours looks to be the main threats from the stronger storms. High temperatures into the lower 80s on Wednesday will be a last warm spell in a while, as more clouds than sun, and daily chances for showers will help make for cooler temperatures (aided by longer fall nights). Temperatures on Thursday should finally range a tad below seasonable norms into the lower 70s. Colder air finally making its mark on the Valley will bring low temperatures into the mid and upper 40s Thursday night - showing that autumn conditions have finally arrived. .LONG TERM...(Thursday night through Monday) Issued at 405 PM CDT Tue Oct 9 2018 Another Pacific hurricane, Sergio is forecast to become absorbed into the western trough late this week, helping the trough to remain over the Baja region into early next week. For this region, drier and cooler conditions will prevail for the remainder of the work week, as high pressure building in from the NW controls the weather situation. The high exiting to the east during Saturday will bring back a return southerly flow. This southerly flow, a moisture return, and approach of another system ejecting from the upper system to our SW, will also bring back clouds and rain chances to begin a new week - for Sunday and Monday. Unlike earlier this week, high temperatures should be in the 60s on Friday, warming back into the 70s for the weekend and early next week. Lows will mostly range in the 40s and 50s. && .AVIATION...(For the 00Z TAFS through 00Z Wednesday evening) Issued at 651 PM CDT Tue Oct 9 2018 An area of scattered showers continues to push northwest across central Georgia. VFR cigs between 3000 and 5000 feet are primarily associated with this activity, with some pockets of IFR cigs. Overall though this activity has been becoming less widespread. Thus have less confidence that -SHRA will directly affect either terminal with this activity and be more scattered as in moves across Alabama. Thus only lowered cigs to MVFR between 07Z and 12Z at terminals. Based on most guidance, these MVFR cigs should linger through much of the day. By late in the period (KMSL~18Z and KHSV~21Z) -SHRA ahead of an approaching front will push into both terminals. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...NONE. TN...NONE. && $$ SYNOPSIS...RSB NEAR TERM...RSB SHORT TERM...RSB LONG TERM...RSB AVIATION...KTW For more information please visit our website at weather.gov/huntsville.