FXUS63 KJKL 152156 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 556 PM EDT Thu Oct 15 2026 .KEY MESSAGES... - Showers remain possible at times through Friday night. - Much cooler weather arrives for the weekend - the coldest we have experienced so far this autumn. This poses a risk for frost on Saturday night into Sunday morning. && .SHORT TERM...(This evening through Friday night) Issued at 445 PM EDT THU OCT 15 2026 Late this afternoon, an upper level ridge was centered off the Southeast US Coast and extended from the Atlantic into the Southeast Conus. Further west, upper level troughing extended from near Hudson Bay into the Plains to Central Plains. At the surface, a boundary that had stalled out over the area earlier in the day was lifting to the northeast as a warm front in advance of a sfc low tracking from the mid MS Valley vicinity toward the Great Lakes. Isolated mainly weak convection was occurring from the Bluegrass region east near the I-64 corridor into western West Virginia. A few sprinkles were occurring further south. Late afternoon temperatures ranged from the upper 80s near the TN border to the mid to upper 70s in the north and east. The upper level ridge will become centered off the southeast U.S coast tonight and tomorrow which will allow the upper level trough to approach the eastern Conus from the west. An initial shortwave should pass northwest of eastern KY tonight, while the main trough axis progresss into the western Great Lakes to mid MS Valley tonight and then reaches the eastern Great Lakes to Lower OH Valley to Gulf coast vicinity on Friday evening. This will be preceded by the previously mentioned sfc low tracking across central sections of the Great Lakes to the St Lawrence Valley. The boundary currently lifting north will move north and east of eastern KY this evening. Meanwhile, the trailing cold front will progress across the Commonwealth tonight through midday on Friday, crossing eastern KY during the day. Chances for showers wane this evening, with the boundary moving north and loss of daytime heating. With a moist airmass in place and the approaching cold front, mild overnight lows compared to mid October normals are anticipated for tonight. Highs for Friday occur during the morning, before temperatures drop by midday into the afternoon on west to northwest winds. Cooling temperatures aloft and the approach of the upper trough and passing front will result in shower chances for Friday with light amounts. The upper trough continues east and crosses eastern KY on Friday night particularly nearer to the VA border. Lingering low level moisture and upslope flow will result in chances for showers/light rain lingering Friday evening into Friday night. Lows will be cooler than recent nights in the upper 30s to mid 40s. .LONG TERM...(Saturday through Thursday) Issued at 555 PM EDT Thu Oct 15 2026 The central theme of the long term forecast period is the advection of a cooler and drier airmass into Eastern Kentucky on Saturday. In the wake of Friday's FROPA, a building surface anticyclone will yield northerly and then east-northeasterly surface winds across the forecast area this weekend. Combined with northwesterly flow around the backside of the mean troughing aloft, this shift will end the production of any lingering upslope rain showers by midday Saturday. A modified continental polar airmass moves into the region in its wake, and temperatures will likely struggle to get much warmer than the mid 50s in Eastern Kentucky on Saturday afternoon. Increasingly efficient diurnal mixing could lead to breezy wind gusts up to 20mph, but it should also help to scatter out the remaining clouds by Saturday evening. This, in turn, sets the stage for efficient radiational cooling overnight, and the area appears primed for the first significant frost of the season by Sunday morning. As a reminder, the criteria for a Frost Advisory is defined as minimum shelter forecast temperatures between 33 and 36 degrees Fahrenheit during the growing season, on nights with good radiational cooling conditions like light winds and mostly clear skies. The aforementioned postfrontal surface high moves overhead on Saturday night, leading to a lighter gradient winds and further reinforcing the notion that the area will see clear skies on Saturday night. The NBM ensemble data continues to resolve a 60-90% chance for minimum temperatures to fall below that 36 degree criterion, and frost headlines are likely to be issued soon. With that being said, the magnitude of the frost will likely be somewhat elevation-dependent. Confidence in widespread frost is greatest in the most sheltered and shaded valley locales, which could make a run at the 32 degree mark. There remains a 20-40% chance within the ensemble data for temperatures to reach the freezing point in the coldest hollows. A freeze is not the most likely forecast solution in our CWA, but given that some of the station-specific MOS guidance explicitly drops temperatures to near 30, trends in the incoming higher-resolution forecast guidance will need to be monitored. With that being said, most of the broader and more populated valley locales across our CWA will experience at least areas of frost on Saturday night. The frost will be patchier atop ridges and in places closer to the mainstem rivers and lakes. Bodies of water intrinsically hold onto heat for longer, and it remains plausible for there to be some patchy river valley fog in their immediate vicinity. This fog would counteract frost formation, so confidence in frost is lowest in places immediately next to the Kentucky, Cumberland, Licking, and Levisa/Tug Fork Rivers. Agricultural interests and recreational gardeners should be prepared to take protective actions for any sensitive plants in this time frame, and they are encouraged to continue monitoring for forecast updates and potential product issuances. While Saturday and Saturday night remain the coldest part of the forecast period, there has been a noticeable trend towards slower airmass modification in next week's forecast guidance. More and more ensemble members are pinching off a shortwave within the mean Eastern CONUS troughing on Sunday. That feature spins into a cutoff upper level low over the Mid-Atlantic in the initial stages of the next work week. The presence of this feature will block/delay the eastward propagation of a mid/upper level ridge in the Ozarks, which, in turn, will prevent temperatures from quickly rebounding into the 70s in our forecast area. Rather, temperatures will gradually rise towards afternoon highs in the 60s on Sunday, Monday, and Tuesday. Some patchy frost is possible in the favored hollows at night, but the overarching warming trend (albeit slower) will eventually favor lows in the 40s and valley fog. With fair skies in the forecast, Eastern Kentucky should get to enjoy a prolonged period of quiet autumnal weather early next week. The forecast becomes more uncertain for Wednesday and beyond. There are diverging model solutions surrounding that low pressure system's evolution, with some guidance even suggesting a potential hybrid tropical cyclone along the east coast. Others take the low out to sea, which would allow the building southern CONUS ridge to exert more influence over the Ohio River Valley. It is difficult to pinpoint specific temperature forecast details towards the end of the period as a result, but both camps favor dry weather in the region. The CPC Days 6-10 and Days 8-14 Outlooks resolve a 40-60% chance of below-normal precipitation in Eastern Kentucky, and climatologically speaking, this is already the driest time of the year here. D0 "Abnormally Dry" conditions were expanded across portions of the commonwealth in today's Drought Monitor update. Expect these contours to be maintained or perhaps even expand as this dry pattern sets up and potentially persist through the end of the month. Fire weather interests are encouraged to monitor for future updates on that topic as the time approaches. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) ISSUED AT 155 PM EDT THU OCT 15 2026 At issuance time, VFR was reported for southern TAF locations such as KSME and KLOZ, while MVFR to IFR, and in some cases lower reductions were reported in locations further to the north including KJKL, KSJS, KIOB, and KSYM. A few showers were moving across northern and eastern sections as a boundary continues to lift back north. With daytime heating, gradual improvements should occur during the fist 6 hours of the period for the 4 more northern TAF locations with VFR continuing in the south. Also, additional scattered showers and perhaps a thunderstorm may develop and affect KSJS, KIOB, KJKL, and KSYM during the first 6 hours of the period. Chances for showers diminish quickly thereafter, with mainly VFR anticipated between 00Z and 12Z. A cold front will near and move across the area to end the period. This will likely bring a return of low clouds including some MVFR or perhaps lower ceilings and the chance for showers. Winds will average south to west at generally 10KT or less through 12Z, before becoming westerly at 6 to 12KT. && .JKL WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...JP LONG TERM...MARCUS AVIATION...JP