textproduct: Jackson

KEY MESSAGES

- A more active weather pattern will set up this week, with multiple chances for widespread showers and storms from Monday night through Wednesday.

- Severe weather potential remains masked by forecast uncertainty here in Eastern Kentucky, but a stronger line of storms is poised to approach the I-75 corridor early on Tuesday morning.

- Additional thunderstorms are possible later on Tuesday and again on Wednesday, and these will bring highly beneficial rainfall to the region.

- Once a frontal boundary finally clears the area late next week, cooler than normal temperatures are favored.

UPDATE

Issued at 900 PM EDT SUN APR 26 2026

Forecast remains on track. Quiet conditions are expected this evening with mostly clear skies. Diurnal temperature curves were refreshed with the latest observational data from around the area.

LONG TERM

(Tuesday through Sunday) Issued at 708 PM EDT Sun Apr 26 2026

When the long term forecast period opens on Tuesday morning, the main line of activity discussed above will likely be pushing out of of our forecast area. Its parent cold front is poised to stall out in the vicinity of the Ohio River as it gets abandoned by its upper level support overnight, adopting more of a zonal orientation in the process. This boundary could serve as the focal point for additional showers and storms on Tuesday afternoon/evening, but there are several limiting factors at play. The boundary's increasingly diffuse nature means that its forcing will be rather weak at first. The wind grids are rather uniform, as this afternoon's forecast guidance suite collectively resolved persistent and breezy southwesterly low level flow spreading across the forecast area by midday. After a cool start to the day in the upper 50s, the warm air advection associated with these winds will allow temperatures to recover into at least the mid 70s by Tuesday afternoon. It is uncertain how much warmer than that it will get, and forecast highs have actually ticked a bit downwards relative to this time yesterday. Some of this uncertainty is rooted in the amount of cloud cover that lingers after the AM activity, especially in southeastern portions of the forecast area. There, lighter rain may linger behind the line for a few hours, meaning that they will. experience less solar insolation than areas that clear out quicker. As such, relatively cooler temperatures are forecast closer to the VA state line, but this may yield a differential heating boundary. If that boundary begins to shift north during the afternoon WAA, a locally enhanced area of convergence could emerge, but otherwise, it will take reaching convective temperature thresholds (generally in the upper 70s) to trigger CI on the warm side of the boundary. The currently available deterministic BUFKIT soundings are mixed on whether or not this threshold is met at sites in northern and western sites around the CWA, but any cells that do develop could take advantage of the modeled 40 knots of 0-6km shear to become organized into supercell-esque structures. This activity would be inclined to propagate east-southeast into the cooler air across SE KY, and interactions with any mesoscale boundaries will need to be watched closely. Modeled hodographs show some modest low-level curvature, but they are generally linear. This suggests that hail and damaging winds would be the primary hazards with any discrete convection, unless a right- mover is able to facilitate a mesoscale accident. Convective trends will need to be monitored closely on Tuesday afternoon as higher resolution guidance becomes available, but the discrete thunderstorm risk currently appears conditional.

There will be another chance for strong to severe thunderstorms on Tuesday evening as a shortwave ejects out of the Ozarks and into the Lower Ohio/Tennesseee River Valleys. Ahead of this feature, moisture will be pooling on the south side of the stalled boundary. This results in a crescent-shaped corridor of dewpoints above 60 degrees stretching from the Lake Cumberland region through the I-75 corridor and into the Bluegrass region along I-64. In the mean LREF data, this corresponds with a narrow tongue of 1000-1500 J/kg of MUCAPE by 8PM Tuesday evening. The dynamic lift provided by the approaching negatively-tilted trough should combine with strong midlevel flow to provide enough lift and bulk shear for organized storm clusters. These clusters will want to ride the instability gradient into our CWA from the west. The greatest CAPE values are generally resolved in southwestern portions of our CWA, near Lake Cumberland, and SPC has placed Wayne, Pulaski, McCreary, and Whitley counties in a Slight (Level 2/5) Risk for severe storms on Tuesday. The rest of the forecast area is denoted in a Marginal (Level 1/5) Risk, largely due to the conditional nature of the afternoon risk and the potential for multiple failure modes. One of the factors that could result in a forecast bust is convective cloud debris blowing off stronger convection to our southwest in the Tennessee Valley. Machine learning guidance is more aggressive with the severe probabilities to our southwest, and the activity there could rob us of the necessary instability for stronger storms. The core of the nocturnal low-level jet with this system is also relegated to the Tennessee Valley. This reduces the amount of low-level shear available to storms, so damaging wind gusts and hail would be the primary hazard types with any sustained storm clusters on Tuesday evening. It is also plausible that that upstream activity once again weakens as it moves into our CWA, and Tuesday's afternoon/evening convection will remain a low-confidence forecast until the exact evolution of the morning activity becomes clear. Any convection that occurs on Tuesday will cause the stalled boundary to creep towards the south, as will the ejection of Tuesday night's shortwave. The surface low associated with this disturbance will move through the Ohio River Valley on Wednesday morning and pull the boundary southeast into the CWA. Depending on what time FROPA occurs, one last round of thunderstorms is possible in our CWA on Wednesday afternoon. That forecast is shrouded by the compounding uncertainty from Monday and Tuesday, but the further south and east one goes into the CWA, the more likely this third round of activity becomes. The approaching front, the digging of a more robust trough aloft, and the area's positioning in the vicinity of the left exit region of a 300mb jet streak should provide enough lift for precipitation. Likewise, the strength of the midlevel flow should maintain the approximately 40 knots of effective bulk shear. The thermodynamic environment is highly uncertain though. While Tuesday night's cloud cover will insulate lows to readings around 60 degrees, there is less of a signal for skies to clear after sunrise on Wednesday morning. Forecast highs are notably cooler (upper 60s to lower 70s) on Wednesday than the previous two days, which keeps the mean LREF instability values in the 500-1000 range. A HSLC (high shear, low cape) type set-up cannot be ruled out with any frontally forced convection, but the available ML/AI/Analog guidance only resolves low-end, marginal-type severe probabilities across the southeastern third of the forecast area on Wednesday. At the very least, this third round of activity will cement the notion that some highly beneficial rainfall is in store for Eastern Kentucky this week. As convective-allowing models enter the ensemble blend used t populate the storm total QPF grids from Monday evening through Wednesday night, forecast rainfall totals have become more spatially variable. Localized, streaky maximums have emerged in locales where models track multiple rounds of convection, but the highest totals are generally confined to the Cumberland River Basin. The LREF ensemble probabilities for at least than 1 inch of precipitation from all of this activity have trended downwards with the last two model cycles, but greater than 50% probabilities remain in the vicinity of Lake Cumberland and in the Bluegrass region. These are the same areas with the highest dewpoints leading into Tuesday evening's rainfall, and climatologically speaking, they experience more efficient moisture return. In the Big Sandy Basin and along the Virginia state line, the probabilities have decreased to between 40 and 50%. This is likely due to the effects of downsloped southeasterly flow ahead of Monday night's precipitation, which yields locally drier air in the lower levels and undercuts accumulation via evaporative processes. The final round of precipitation may make up for this, but when all is said and done, the area's QPE minima is likely to come in the eastern portions of the CWA. However, a wetting rain (> 0.25 inches of precipitation) is almost certain, with > 95% probabilities resolved area-wide for this threshold. All rain that falls will prove highly beneficial to the ongoing drought across Kentucky, and it should quench some of the earlier spring fire weather concerns. The antecedent dryness does mean that the ground should be able to soak up most of the precipitation that falls, but given the potential for multiple rounds of convection, WPC has maintained a Marginal (Level 1/4) Excessive Rainfall Outlook for the southern half of the CWA on Tuesday. Widespread fluvial flooding remains unlikely, but nuisance ponding of water cannot be ruled out in urban corridors and the typical poor drainage areas.

Deeper mid to upper level troughing digs into the Ohio River Valley headed into the weekend. Strengthening WNW flow aloft will work to advect a cool, continental airmass into the forecast area, and the aforementioned, stubborn frontal boundary is poised to finally shift out of the CWA on Thursday. Precipitation chances and sky cover tapers off as drier air filters in throughout the column, giving way to highs in the 60s and lows in the 40s. These readings are below climatological norms for Eastern Kentucky at the end of April, and reinforcing shots of colder air arrive in the region as shortwave disturbances rotate around the base of the broader troughing to kick off the month of May. The odds for precipitation with these disturbances appear to be decreasing, and there has been a trend towards a cutoff upper level low developing in the NE CONUS next weekend. Such a pattern favors below normal temperatures in Eastern Kentucky for the first days of May. The CPC extended-range hazard outlook is centered around these colder temperatures due to their potential to cause a frost, and their 6-10 day temperature outlook now highlights a 60-70% chance of below normal temperatures across the greater Ohio River Valley. Those with interests sensitive to frost (such as agricultural crop producers or recreational gardeners) are accordingly encouraged to continue to monitor for updates as the calendar turns to May. As of the time of writing, the coldest nights look to be in the May 2nd to May 4th time frame.

AVIATION

(For the 00Z TAFS through 00Z Monday evening) ISSUED AT 703 PM EDT SUN APR 26 2026

VFR conditions should prevail through the TAF period. Expect mainly high clouds at times. Fog is possible tonight in the most sheltered river valleys but is not expected to impact the TAF sites. Winds will generally be light and variable at less than 10 kts through tonight before becoming southerly at 5 to 10 kts after 14Z on Monday.

JKL WATCHES/WARNINGS/ADVISORIES

None.