textproduct: Jackson

KEY MESSAGES

- Showers and thunderstorm chances will persist through the middle of the new work week. The greatest coverage is expected from Tuesday through Friday. Some of those storms could arrive as organized clusters and a potential for strong wind gusts. - Isolated heavy to excessive rainfall may occur where storms are most persistent leading to elevated concerns for flooding later in the week.

UPDATE

Issued at 740 AM EDT SUN AUG 9 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 near term PoPs to capture the ongoing stray storms in the east. These minor adjustments have been sent to the NDFD and web servers along with a freshening of the SAFs and zones.

LONG TERM

(Monday night through Saturday) Issued at 440 AM EDT SUN AUG 9 2026

The latest model data continue to indicate that the pattern aloft will favor the formation of storm clusters any of which could intrude on the weather for eastern Kentucky later in the new work week. Right now SPC has Tuesday highlighted as the greatest concern for severe weather (damaging winds) from this development with a Slight Risk outlined in our northeast counties. Please continue to monitor this potentially impactful weather situation.

The previous long term discussion follows:

The long term forecast period starts out on a seasonably hot note in Eastern Kentucky, with synoptic conditions favoring efficient diurnal warming. When the period opens on Monday morning, the area will be positioned between a building ridge over the Southern Plains and the subtropical ridge over the southeastern states. Models collectively resolve midlevel height rises over the commonwealth on Monday as the influence of the former feature grows. Both diabatic and adiabatic warming processes will allow temperatures to climb towards the upper 80s/lower 90s on Monday. These seasonably hot highs will combine with the antecedent moisture (dewpoints in the 70s) to yield widespread heat indices in the 90s. A few triple digit readings cannot be ruled out, but heat headline products are not anticipated.

The temperature forecast is partially compromised due to increased rain chances on Monday in southern portions of the forecast area, which may cause localized pockets of rain-cooled air and cause highs to under-perform. As the col previously noted between the two synoptic ridges closes up on Monday, it will push a subtle upper level disturbance towards the Tennessee River Valley. This feature's alignment with peak diurnal heating has introduced isolated to scattered coverage PoPs (15-35%) across the counties along the TN and VA state lines. Due to the previously- discussed and increasing influence of the dominant ridging features, this activity should not pose a risk for any significant impacts. Rather, a few run-of-the-mill late summertime showers and thunderstorms cannot be ruled out on Monday afternoon/evening.

The flow aloft is progged to turn more northwesterly overnight into Tuesday morning, which will allow a series of shortwave impulses to navigate around the ridge and into the forecast area. Pattern recognition suggests that the convection associated with these disturbances could take the form of MCSes moving through the Midwest and the Greater Ohio River Valley. The first of those thunderstorm complexes could affect far northern portions of the forecast area late Monday night into Tuesday morning, and SPC has accordingly delineated a Marginal (Level 1/5) Severe Weather Outlook in Fleming and Rowan Counties for the period ending at 8AM Tuesday. Damaging wind gusts would be the primary hazard type in this type of setup, but it is uncertain how strong each complex will be by the time it arrives in the JKL CWA. The first one will be arriving during the diurnal instability minima, and it will probably be in a weakening state as a result. It remains difficult to pinpoint the timing details surrounding each shortwave, and it is equally difficult to determine where any residual outflow boundaries and/or instability gradients might set up in the wake of each storm complex. Forecast uncertainty accordingly compounds as the week progresses.

With that being said, interests are encouraged to remain weather aware on Tuesday and Wednesday. The available medium-range machine learning models and analog-based convective guidance still paint risks for severe weather across portions of Eastern Kentucky on these two days. Once again, damaging wind gusts would be the favored hazard type in such a setup, but mesoscale effects could cause the favored risk areas to shift and other convective hazards cannot entirely be ruled out. Any severe weather risk will be accompanied by a threat for excessive rainfall, and WPC has already delineated a Slight (Level 2/4) Excessive Rainfall Outlooks for portions of the commonwealth on both Tuesday and Wednesday. Flash flooding could develop if storms engage in training and/or backbuilding behaviors. Given the compounding nature of the forecast uncertainty surrounding this setup, it is too early to advertise specific rainfall totals. Instead, we will need to monitor the output of higher-resolution forecast models for parameter spacing that favors those behaviors. The first MCS enters the temporal range of the long-range CAMs tonight, and as more data becomes available in the coming days, forecast confidence should improve.

All of this activity will culminate in the approach of a cold front towards the end of the period. In general, increased late week cloud cover should work to suppress the early week heat as time passes. Temperatures are forecast to modulate back towards more climatologically-appropriate values by Thursday. Expect highs to return to the mid/low 80s on Thursday, Friday, and Saturday and lows to fall somewhere between the mid 60s and near 70. Precipitation chances are more uncertain, as the extended forecast guidance suite is split on how progressive that boundary will be. If it is slower and/or becomes diffuse over the CWA, rain chances will persist into the weekend. If guidance trends towards a more progressive pattern aloft, the broad-brushed PoPs currently in the grids for Saturday could trend downwards. The 12z Euro currently portrays the former solution, whereas the 12z GFS resolves the latter, with a drier continental airmass advecting into the area via more northerly flow. Their ensemble counterparts are met with increasing model spread, and it will be interesting to see which camp becomes more favored as the uncertainty surrounding the mid-week MCSes subsides.

AVIATION

(For the 18Z TAFS through 18Z Monday afternoon) ISSUED AT 224 PM EDT SUN AUG 9 2026

Isolated convection is occurring at TAF issuance. Otherwise, primarily a low-end VFR cumulus field has bubbled up across the the region with a layer of mid-level clouds noted over much of eastern Kentucky as well. Convection looks to remain isolated to widely scattered and confidence in impacts was too low for inclusion at the TAF sites. These showers and any thunderstorms will dissipate this evening with the loss of diurnal heating. Fog formation can be expected in the more sheltered river valleys overnight but should not reach the TAF sites. The remnants of an MCS could then impact northern TAF sites toward the end of the period. Winds will generally be southwesterly at less than 10 kts through the period; however, locally strong and gusty winds can be expected near any storms.

JKL WATCHES/WARNINGS/ADVISORIES

None.