FXUS63 KJKL 150626 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 226 AM EDT Thu Oct 15 2026 .KEY MESSAGES... - Temperatures remain mild through Thursday, while showers are possible at times into Friday. - A few thunderstorms capable of locally heavy rain and strong wind gusts are possible this evening. - Much cooler weather arrives for the weekend - likely 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 Thursday night) Issued at 445 PM EDT WED OCT 14 2026 Late this afternoon, an upper level ridge extended across portions of the Southeastern Conus and into sections of the Gulf. Further west an upper level low was over the Four Corners vicinity. Meanwhile, a shortwave trough/MCV was moving through the OH Valley and interacting with a boundary sagging toward the Commonwealth. With the ridge in place to the south, it was another day of record or near record warmth in eastern KY with highs having reached into the 80s in most locations. At JKL, the high so far has been 86, breaking the previous record of 82 from 2017/2021. Showers and a few storms associated with the sagging cold front and the shortwave trough/MCV passing by to the north have moved into northern sections of the region over the past couple of hours. Low level lapse rates are analyzed around 6.5 to 7C/km in the north with mid level lapse rates a bit on the meager side in the 5.5 to 6C/km range. MLCAPE across the region is analyzed on the modest side in the 500 to 1000 J/kg range while effective shear per SPC mesoanalysis page is on the order of 25 to 30KT in the north. PW meanwhile was recently analyzed near 1.3 inches along the VA border and around 1.9 inches in the far northwest. Upstream of the area, a wind gust to 39 mph was observed at the KY Mesonet site in northern Fayette County. This evening and tonight, the shortwave trough/MCV working through the OH Valley will move east of the area during the evening while the upper low initially over the Four Corners region should move into northeastern CO. Meanwhile further north, a shortwave will move southeast from Alberta across sections of Saskatchewan and into Manitoba and the Northern Plains. At the same time, the frontal zone will sag into eastern KY and stall out over the middle of the region. With PW expected to remain elevated and increase to the 1.9 to 2.1 inch range or in the 97th to 99th percentile range, if any training of thunderstorms were to occur it could result in locally heavier rain. With some modest instability in place as well, a storm or two this evening could result in a strong wind gust. In general, this potential is greatest near and north of the Mtn Parkway. WPC has a slight ERO in the northern sections of the area while northern areas are also in a marginal SWODY1. Otherwise, near and behind the sagging front, lowering clouds and patchy fog or stratus build down should occur as the night progresses and this will linger into Thursday morning with the boundary in the vicinity. Showers remain possible tonight near the boundary as well. For Thursday and Thursday night, the upper low that will have reached CO late tonight should weaken to an open wave and eventually merge with the trough to its north during this timeframe. This resulting 500 mb trough axis should reach Ontario to the western Great Lakes to Central Plains through late Thursday night. As this occurs, a sfc low should track from sections of the Plains to the Central to eastern Great Lakes through Thursday night. The boundary that will have stalled over eastern KY will lift back north as a warm front, while a cold front enters the Commonwealth on Thursday night. Shower chances linger into Thursday nearthe boundary before it moves north Thursday evening. A thunderstorm cannot be ruled out as well. South of the boundary, temperatures will remain mild, with highs likely to climb back well into the 80s for Thursday highs. With the front approaching, winds and gusts should increase late particularly in the west. .LONG TERM...(Friday through Wednesday) Issued at 616 PM EDT Wed Oct 14 2026 When the long term forecast period opens on Friday morning, Eastern Kentucky will be on the precipice of a significant change in airmass. A robust, positively-tilted trough stretching from the Central Plains to the Upper Midwest will dig deeper into the Ohio and Tennessee River Valleys as the day progresses. At the surface, this translates to a deepening cyclone over the eastern Great Lakes and a sharp cold front trailing behind it. That cold front will be the focal point of Friday's forecast, with sensible weather details such as high temperatures and wind direction dependent upon a given place's position relative to the boundary. The entire CWA will experience mild AM lows in the upper 60s on Friday morning, when forecast guidance collectively resolves the boundary off to the west in the Bluegrass. Pre-frontal surface winds will be out of the southwest. So will the flow aloft, and this vertical continuity suggests that there will be warm air advection ongoing on Friday in places out ahead of the front. FROPA has trended a little bit later in the day, and Friday's forecast highs have accordingly risen a few degrees towards the upper 70s in our easternmost counties. In counties further to the north and west, there will be a shorter window of time where this WAA overlaps with the diurnal warming cycle. So, high temperatures in places like the Bluegrass will only be a few degrees warmer than those lows (in the upper 60s/lower 70s). Those highs will also likely occur much earlier in the day than usual, as once FROPA occurs, diurnal heating will become suppressed by cloud cover and a sharp wind shift. Surface winds should shift towards a westerly and then northwesterly orientation as FROPA occurs from west to east on Friday. Frontal and orographic lift will combine to yield additional light rain shower chances along and behind the boundary, but the bigger story with this boundary will be the robust cold air advection that takes place behind it. Given the tightening pressure gradient of the parent synoptic system, Friday afternoon's post-frontal winds will be quite breezy. The REFS high-resolution ensemble resolves a 50-80% chance of wind gusts in excess of 25 mph across most of the JKL CWA in this time frame. When this criteria is lowered to >20 mph, the probabilities jump to near 100%. If it is raised above 30 mph, the odds dwindle off significantly. While wind advisory criteria is unlikely to be met, the magnitude of these winds reinforces the notion that there will be an efficient cold air advection regime in the wake of Friday afternoon's frontal passage. Expect a significant drop in temperatures to occur on Friday evening, with temperatures in the 50s area-wide by sunset. Once the sun goes down and solar insolation goes away, the temperature plummet will continue. The entire CWA should wake up to temperatures in the 40s on Saturday morning, but lingering cloud cover and some upsloped rain showers should prevent it from getting much colder than that. The same cannot be said for Saturday night/Sunday morning, which looks to be the coldest night of the autumn season thus far. As a post-frontal surface high pressure system builds into the CWA on Saturday morning, winds will shift to a more northerly orientation. This will bring an end to any orographically-enhanced post-frontal rain chances, and a much cooler/drier continental airmass will move into the region in the wake of the precipitation. Highs will struggle to get much warmer than the 50s, and dewpoints will plummet into the 30s on Saturday afternoon. Diurnal mixing should work to erode any lingering cloud cover by sunset, which should set the stage for efficient radiational cooling overnight. NBM ensemble data resolves a 60-90% chance of temperatures dropping below 36 degrees across most of the JKL CWA overnight. The most sheltered and shaded valleys could make a run at the 32 degree mark, but the probability of occurrence drops to below 40% at this threshold. 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. Saturday night is poised to meet this criteria, so agricultural interests and recreational gardeners are encouraged to monitor for potential product issuances as the time approaches. Temperatures will be slow to make a full recovery back above the 70 degree mark next week, although a gradual warm-up is expected. The postfrontal high should shift east on Sunday as the mid/upper level trough axis aloft swings through New England. Antecedent forecast thinking is that a building ridge will allow temperatures to moderate back into the 60s under fair skies by early next week. However, some of the more recent pieces of guidance (namely members of the Euro ensemble) are developing a cut-off low over the Carolinas in this time frame. That feature could block the eastward propagation of that ridging, and it would cause temperatures to stay on the lower side of the forecast envelope early next week. Nevertheless, fog should become favored over frost in the valleys at night as temperatures warm. This is typical for autumn in Eastern Kentucky, and next week's forecast features temperatures much closer to normal than what we are experiencing at the present moment. && .AVIATION...(For the 06Z TAFS through 06Z Thursday night) ISSUED AT 226 AM EDT THU OCT 15 2026 Light to moderate rain lingered mainly in portions of southeast KY at the start of the period-- the remains of a line of thunderstorms which moved through much of the area. The precipitation is ahead of a very slow moving cold front moving south into KY. Many locations were seeing IFR or worse conditions where the precip moved through, and especially near/north of I-64. However, some places were still VFR, especially over south central KY. The remaining precip will be tapering off, but largely the status quo is expected for conditions into the day, with some variability up and down. There still could be some additional showers as well. The cold front will stall in eastern KY during the day and then turn back north as a warm front by evening. As the front heads back north, overall improvement is expected from south to north. VFR conditions are forecast to return area wide from south to north during the afternoon and early evening. && .JKL WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...JP LONG TERM...MARCUS AVIATION...HAL