FXUS64 KMRX 170556 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 1256 AM EST Wed Dec 17 2025 ...New DISCUSSION, AVIATION... .KEY MESSAGES... Updated at 1229 AM EST Wed Dec 17 2025 - Strong mountain winds, widespread showers, and isolated thunder in the south are expected on Thursday and Thursday night. - Afterwards, drier and cooler conditions return. && .DISCUSSION... Issued at 1229 AM EST Wed Dec 17 2025 A weak ridge aloft remains in place while surface high pressure continues to support dry weather across the southern Appalachians. Mid level stratus deck is moving in from our west which will help keep overnight temperatures warmer than what we've experienced the past few nights, with lows expected to drop near or just below freezing instead of the teens. Warm temperatures will remain in place Wednesday, a few degrees warmer than Tuesday. By Thursday, a deepening trough will dig across the central United States, driving warm and moist air advection into the region. Temperatures will rise above normal, and precipitation chances will increase areawide. Rainfall will initially develop through isentropic ascent, followed by a frontal passage Thursday night. Low associated with this system will track across northern Michigan, and favorable low-level jet orientation of 55–65 kts per latest NAM guidance, mountain wave winds are expected across the East Tennessee mountains and adjacent foothills. Current projections support gusts 50 mph or more. A Wind Advisory appears increasingly likely, with potential to reach High Wind criteria in some isolated spots as the event approaches. Rain will be the primary precipitation type with this system due to the warm temperatures. A few thunderstorms are possible across the southern tier, where some forecast soundings indicate weak elevated instability. Despite limited instability, the strong low-level jet could allow heavier showers to mix down gusts of 30–40 mph, particularly as the main axis forcing moves through. However, the risk of damaging winds remains low. On the backside of the system early Friday morning, light snow may occur if cold air advection and northwest flow align with lingering moisture. Any accumulations would likely be confined to higher elevations given the above-normal temperatures preceding the system heating the ground up in advance. Behind the front, high pressure will return Friday afternoon, bringing drier and cooler conditions. The upper-level flow will become quasi-zonal through the weekend, though weak disturbances could produce occasional light rain. NBM guidance introduces PoPs of 30% or less for the latter half of the weekend into early next week. Any rainfall should be light and non-impactful, with more dry periods than wet. Temperatures will rebound to slightly above normal values over the weekend. && .AVIATION... (06Z TAFS) Issued at 1229 AM EST Wed Dec 17 2025 VFR, dry, and light winds to continue through this TAF period. High clouds to continue to stream in overhead. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 55 39 60 35 / 0 10 80 90 Knoxville McGhee Tyson Airport, TN 53 35 61 35 / 10 10 80 100 Oak Ridge, TN 50 34 59 32 / 10 10 80 100 Tri Cities Airport, TN 50 33 59 34 / 0 0 50 100 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DISCUSSION...99 AVIATION...Wellington