Jackson forecast discussion

Short Term

(Today through Saturday) Issued at 425 AM EDT FRI OCT 16 2026

08Z sfc analysis shows a warm front now east of the state while a distinct and well defined cold front is approaching from the west. This has left mostly clear skies around eastern Kentucky as the showers have moved off to the east with the warm front. With plenty of ground moisture around, and patches of clearing in the skies, areas of fog have developed in the valleys this night and become locally dense. Currently, temperatures are quite mild and running in the low to mid 70s for much of the area with some mid to upper 60s noted in a few valley locations. Meanwhile, amid southwest winds around 5 mph, dewpoints are rather moist and generally in the low to mid 60s.

The models, and their individual ensemble suites, are in excellent agreement aloft through the short term portion of the forecast. They all depict the first full-latitude trough of the season swinging out of the Upper Midwest and into the Ohio Valley this morning. This feature steadily works into Kentucky today while starting to close off overhead later this evening and tonight. A core of energy accompanies the southern extent of the trough as it, and its sharp 5h height falls, move through by 06Z Saturday. Benign northwest flow then follows for the rest of the period. Given the very small model spread, most of the forecast grids came from unadjusted NBM data this morning. However, did incorporate the latest CAMs guidance into the NBM PoPs as the front moves through. With CAA for the bulk of the period did not see much of an opportunity to improve on the temps or dewpoints.

Sensible weather will feature a very changeable day on account of the front moving through early in the day from northwest to southeast accompanied by scattered to numerous showers. Even after the front passes and winds switch more northwesterly, a few showers will linger and only slowly clear out west to east. Temperatures peak early today before falling post-frontal leading to a chilly end of the afternoon and evening amid those lingering showers. There will be an upslope component to the post frontal showers that hold on into the night before finally clearing to the east early Saturday. With this new air mass, temperatures will be much cooler during the day, Saturday, despite plenty of returning sunshine. In fact, many places will see temperatures 20 or so degrees colder Saturday afternoon compared to this afternoon. This, along with strong high pressure moving over the area will set the stage for a very chilly night with frost on tap and even some spots expected to hit freezing by dawn Sunday. A frost advisory will likely be needed.

The main changes to the NBM starting point were to include details from the latest CAMs consensus into the PoPs through tonight. Temperatures and dewpoints were left nearly unchanged.

Long Term

(Saturday night through Thursday) Issued at 440 AM EDT FRI OCT 16 2026

The extended portion of the forecast appears to be on track for the significant frost concerns both Saturday and Sunday nights on account of ridging aloft and strong sfc high pressure in place. This pattern will keep the weather rather quiet for the upcoming week with gradual moderation in temperatures each day following a chilly end to the weekend.

The previous long term discussion follows:

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 06Z TAFS through 06Z Friday night) ISSUED AT 145 AM EDT FRI OCT 16 2026

With the departure of the showers off to the northeast, southwesterly low-level winds and resulting LLWS will be found for a time across the area while a strong cold front approaches from the west. LLWS is most likely for sites north and west of JKL, as the low-level jet will be weakening as it moves east across the area early this morning.

Southwest winds will become more westerly and then northwesterly with the cold front crossing the area during the daytime hours. Expect sustained winds near 15 kts and higher gusts possible at most if not all TAF sites through much of the afternoon as the front passes. The cold front will bring the return of MVFR and poorer conditions along with the chance for -SHRA through evening.

Jkl Watches/Warnings/Advisories

None.

SHORT TERM...GREIF LONG TERM...MARCUS/GREIF AVIATION...CMC/GREIF