textproduct: Jackson

KEY MESSAGES

- Mainly dry weather is expected through the weekend though there remains a chance for showers and thunderstorms later this afternoon and into the evening.

- Warmer temperatures and a greater potential for showers and thunderstorms return early next week.

- These storms could be more organized and strong to severe on Monday afternoon into the night depending on MCS development and evolution to the north of Kentucky.

UPDATE

Issued at 1255 PM EDT SAT JUL 25 2026

These pesky showers continue to move across portions of the Cumberland Valley and Lake Cumberland regions this afternoon. The various guidance has struggled to handle these and really the NAMnest seems to be modeling this idea the best right now. Given this opted to go with some likely PoPs in the SW portions of the CWA for the next couple of hours. However, this may need expanded further given some of the convection noted upstream. Outside of this overall minor updates needed.

UPDATE Issued at 952 AM EDT SAT JUL 25 2026

This morning we are stuck in the more northwest flow pattern aloft and this is sending weak waves through the upper level flow. These weak waves have been kicking off showers and increased cloud cover toward the Lake Cumberland and portions of the Cumberland Valley region this morning. Overall opted to make some mostly minor adjustments to PoPs and sky cover to better handle the latest obs and trends.

UPDATE Issued at 730 AM EDT SAT JUL 25 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 tweak the near term PoPs per the current radar and CAMs guidance mainly adding sprinkles in the southwest parts of the area. These minor adjustments have been sent to the NDFD and web servers along with a freshening of the SAFs and zones.

LONG TERM

(Sunday night through Friday) Issued at 505 AM EDT SAT JUL 25 2026

The main change to the grids for the first part of the extended forecast this morning was primarily to include some more terrain distinctions into temperatures for Tuesday night, though some uncertainty remains as to the anticipated sky cover. Strong 5h ridging to the west still looks to support a glide path for mid- level shortwaves into eastern Kentucky through the start of the new work week. One in particular, on Monday evening and overnight, is indicating a potential for severe weather given a fairly strong wind field, plenty of instability lingering through sunset, and model suggestions of MCS activity possibly reaching northeast parts of the area that night.

The previous long term discussion follows:

The long term forecast will be dominated by upper level ridging centered over the Great Plains, with troughing along the East Coast. Eastern Kentucky will find itself sandwiched between these features, leading to an extensive period of northwesterly flow aloft. A series of shortwaves will traverse this flow, providing a chance for multiple rounds of showers and storms (potentially in the form of MCS activity). However, confidence in the timing or intensity of these impulses remains low, and impacts to the forecast area will remain heavily dependent on the evolution of upstream convection, increasing uncertainty.

On Sunday, increasingly northwesterly winds will work to pull in better quality moisture from the Midwest, allowing dewpoints to climb into the upper 60s and low 70s across the forecast area by Sunday afternoon. Concurrently, mostly clear skies and increasing influence of the upper level ridge aloft will allow temperatures to rise into the mid 80s across the forecast area, allowing for moderate instability to build, although in the absence of forcing to drive convective initiation, rain chances will likely be relegated to an isolated storm or two at most through the daytime hours, if that. Some models are attempting to hint at isolated to perhaps widely scattered storm chances in our southernmost counties on Sunday afternoon, and the thermodynamic environment will certainly be capable of supporting convection. That being said, many models depict height rises at the same time, corresponding with a modest eastward expansion of the ridge aloft, which would inhibit convection. For now, NBM PoPs were retained, keeping rain chances below 10% across the forecast area through the evening.

Forecast uncertainty increases overnight Sunday into Monday as convective coverage increases in the Midwest, with some model guidance suggesting MCS type activity may approach the forecast area as soon as very early Monday morning. That being said, the most favored outcome at this time is that skies remain relatively clear, owing to surface high pressure lingering on the periphery of the forecast area. For now, a modest ridge/valley temperature split was introduced on Sunday night, in addition to typical valley fog, to account for this more likely solution.

Monday and Tuesday appear to offer the most robust storm chances of the period, with additional impulses moving through northwest flow aloft and a continued signal for MCS activity somewhere in the Ohio Valley. Although there is limited agreement in the timing or intensity of these waves, machine learning guidance has generally highlighted a broad area of severe potential from the Midwest into the Ohio Valley early next week, largely driven by the potential for damaging wind gusts associated with any convective complexes. This risk remains highly uncertain, and the current SPC Day 4 and 5 15% contours do not currently include our area (with Mondays risk area north of Kentucky in the Great Lakes region and Tuesdays risk more focused on the Mid Atlantic). That being said, the modeled environment does seem to support the potential for MCS activity to propagate southeast into the forecast area, and should diurnal timing of these waves also be favorable, the parameter space will be capable of supporting strong to severe storms. LREF mean surface based CAPE is in the range of 1500-2000 J/kg on Monday and Tuesday evening, and LREF mean 0-6 km shear is again in the neighborhood of 30-40 kts, enough to support severe weather. Depending on how many rounds of showers and storms we receive, flash flooding could also potentially be a concern, although this remains similarly uncertain; the Weather Prediction Center has assigned a Marginal (Level 1/4) Risk for Excessive Rainfall on both Monday and Tuesday to account for this possibility. In short, there will be multiple chances for rain early next week, and upstream convective evolution, in addition to wave timing, will dictate impacts to the forecast area.

Following potential activity on Tuesday into early Wednesday, rain chances will decrease again as moisture declines courtesy of increasingly northerly to northeasterly winds. High temperatures will generally rise into the upper 80s each day, with surface high pressure building in the vicinity of OH/WV.

AVIATION

(For the 18Z TAFS through 18Z Sunday afternoon) ISSUED AT 156 PM EDT SAT JUL 25 2026

We continue to see a few mainly rain showers moving across the Lake Cumberland region this afternoon. Given this did add in a tempo group for a few hours at SME and LOZ for some lower vis potential. Outside of this most sites will remain VFR for the first 6 hours of the period. There is more questions as we move past 00Z, as the guidance indicates additional convection develops and pushes across the area. Given this kept a prob30 group for later this evening to handle this idea of some vis restrictions. After this opted to add a bit of fog in the IFR to MVFR range as we move toward dawn. This could be more tied to those who see rain this afternoon and tonight, but some of the guidance is quite bold with the idea of lowering vis. This will have to be watched closer tonight and in the next TAF issuance. The winds will mostly be light and variable below 5 knots outside of any convection.

JKL WATCHES/WARNINGS/ADVISORIES

None.