textproduct: Jackson

KEY MESSAGES

- Showers and storms, some with torrential downpours leading to a risk of high water, are possible for areas generally along and south of a Harlan to London to Somerset line.

- Chances for showers and storms will return to areas mainly south of the Mtn Parkway for Sunday through Monday evening.

- Temperatures will average within a few degrees of normal over the next week.

UPDATE

Issued at 140 AM EDT SAT MAY 30 2026

No significant changes were made to the forecast with mainly just the inclusion of the latest obs and trends for the T/Td/Sky grids. Did also fine tune the PoPs through dawn per the current radar and CAMs guidance. These minor adjustments have been sent to the NDFD and web servers along with a freshening of the SAFS and zones.

UPDATE Issued at 1029 PM EDT FRI MAY 29 2026

Made some minor revisions to PoP/Sky and T/Td grids, the former based on latest model and observed trends. Overall, there is no substantive change to the forecast.

UPDATE Issued at 624 PM EDT FRI MAY 29 2026

Updated hourly T/Td grids for the next several hours. Hourly PoPs and Sky grids were already sufficient, so made no changes for now, but will reassess based on radar trends through the evening and adjust accordingly. The forecast overall is in excellent shape, so changes are minimal.

LONG TERM

(Sunday night through Friday) Issued at 122 AM EDT Sat May 30 2026

When the long term forecast period opens on Sunday evening, scattered showers and thunderstorms are likely to be ongoing in Southern Kentucky. After a period of southwesterly low level flow recharges the atmospheric moisture content over the commonwealth during the daytime hours, the approach of a shortwave disturbance should drag a stalled frontal boundary out of the Tennessee Valley on Sunday night. There remains some uncertainty regarding the northern extent of that boundary's influence, but ensemble guidance gives credence to the notion that the greatest rain potential is in the Cumberland River Basin. Expect increased cloud cover across the across the entire CWA by midnight Monday, which should insulate overnight lows to the upper 50s/lower 60s. Northern valleys could decouple after sunset, but given the aforementioned forecast uncertainty, topography-based edits were limited to minor adjustments for the first portion of the period.

The synoptic pattern aloft looks to amplify headed into the next work week. The forecast guidance suite collectively resolves an amplifying ridge over the Great Plains while two distinct troughs dig into the Pacific Northwest and the Eastern Seaboard. As that Eastern trough deepens on Monday, additional shortwave disturbances are progged to rotate around its backside and into the vicinity of the forecast area. These features should combine with the aforementioned boundary to provide enough lift for additional shower and storms in the southern third of the forecast area on Tuesday. Given the relatively weak wind fields, the proximity of the boundary, and the potential for multiple rounds of activity, WPC has maintained a Marginal Excessive Rainfall Outlook on Monday for counties along the Tennessee State Line. Thankfully, the impulses aloft will shunt this surface boundary back to the south by Monday evening and place the forecast area in a regime of vertically- stacked northerly flow.

These northerly winds will usher a much drier airmass into the forecast area for the rest of the work week. The omega blocking pattern produced by the three synoptic features discussed above will steadily break down as the week progresses. Here in eastern KY, this initially places us on the western periphery of a closed low spinning over New England, with the Central CONUS ridge situated upstream. The gradual eastward propagation of both will leave the northerly flow regime in place through at least Thursday morning. This means that a continental airmass is poised to dominate the sensible weather forecast for Eastern Kentucky next week.

Topography-dependent forecast intricacies will be on display next week, with widespread ridge-valley temperature splits probable from Monday night onward. Valley fog will be possible wherever there is access to a moisture source, be it antecedently wet grounds or a nearby river/creek/stream. The exact values of the overnight lows will be dependent upon the magnitude of diurnal mixing that is realized. The deterministic NBM used to populate the long term grids is on the higher end of the forecast guidance envelope when it comes to dewpoint temperatures. Dry air advection and increasingly efficient diurnal mixing may culminate in dewpoints lower than the upper 40s/lower 50s current depicted in the grids. The currently available BUFKIT soundings and explicitly-mixed sfc->30mb AGL dewpoint model data suggest that dewpoints in the upper 30s/lower 40s are plausible in this pattern. Light winds and recently-wet fuels should curtail any resultant fire weather concerns, so the primary impacts from these drier dewpoints will be the potential for locally cooler overnight lows in sheltered/shaded valleys and the fact that it will feel FANTASTIC outside next week. MaxTs should remain in the 70s for most locations through midweek, with LREF probabilities for highs above the 80 degree mark remaining below the 50% threshold through at least Thursday. Thanks to the low moisture content of the continental airmass, apparent temperatures will be equivalent to the seasonably cool values observed on the thermometers. Thus, under mostly sunny skies, the mid-week weather forecast looks ideal for any outdoor activities that interests might have planned.

The blocking pattern is expected to fully break down by the end of the forecast period, with a flattening ridge eventually settling into the SE CONUS. This would place the Ohio River Valley in quasi- zonal flow aloft and on the backside of the related surface high pressure system. While models disagree on the arrival time of these synoptics (the GFS suite wants to keep the East Coast troughing around for longer), it should yield a late-week warming trend and a gradual increase in atmospheric moisture content. Confidence is growing that highs will return to the 80s area-wide on Friday (60- 80% chance in the latest LREF data), and with the warmth comes the return of summertime PoPs. While the forecast does not currently call for a week-end washout, isolated to scattered pop-up showers and storms return to the forecast to close out the long term forecast period. Meteorological summer starts on Monday, June 1st, and this particular forecast meets the moment.

AVIATION

(For the 06Z TAFS through 06Z Saturday night) ISSUED AT 205 AM EDT SAT MAY 30 2026

A stationary front/boundary has sharpened from near Lake Cumberland and KSME east-southeast to about KI35 (Harlan) this past evening becoming the focal point for low clouds and shower and thunderstorm activity that continues through the rest of the night through late morning period. PROB30, prevailing, and TEMPO groups were used to cover this convective potential, but thunder chances were under 30 percent and thus too low for a mention at any particular terminal. Drier air moves into the area toward midday, forcing this boundary south into Tennessee as a cold front. Meanwhile, a secondary cold front will move south into the area to end the period. Despite these frontal passages, light winds are expected through the night and into the morning before becoming northeasterly at less than 10 kts during the afternoon hours.

JKL WATCHES/WARNINGS/ADVISORIES

None.