textproduct: Jackson

KEY MESSAGES

- Unsettled weather will continue through tonight as a front remains stalled in the vicinity of eastern Kentucky.

- Locally heavy rainfall is expected at times this afternoon into the evening, which could lead to isolated to scattered flash flooding.

- Temperatures will increase to well above normal, or even near record, levels by the middle of next week.

UPDATE

Issued at 740 AM EDT SAT SEP 12 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. These minor adjustments have been sent to the NDFD and web servers along with a freshening of the zones.

LONG TERM

(Sunday night through Friday) Issued at 345 AM EDT SAT SEP 12 2026

At the start of the long term period, a midlevel ridge will be centered over the Southern Plains, with midlevel troughing over the Great Lakes region. Eastern Kentucky will initially find itself between these two features, with relatively zonal flow aloft; however, by Monday, ridging is expected to push eastward and amplify. Meanwhile, at the surface, a cold front will initially be located near the Ohio River. Throughout Monday, this front will sag southward, ushering in cooler and drier air as winds shift to become more northerly to northeasterly. This will keep highs closer to average in the northern forecast area, likely in the low 80s, with warmer temperatures farther south near the TN line. Even so, rain chances with this front look to be relatively low, and any mentionable PoPs remain confined to the northern portions of the forecast area.

Following this frontal passage, there is high confidence an anomalously strong ridge will build into the area and linger through at least midweek, with LREF mean 500 mb heights peaking Wednesday at 599 dam (representing the 100th percentile compared to climatology!). This will suppress convection and keep temperatures unseasonably hot, more characteristic of the middle of summer than mid September. Highs look to peak Wednesday, generally in the low 90s across the forecast area. Also, given increasingly southwesterly winds around a surface high over the Mid Atlantic, dewpoints will quickly rebound, rising into the upper 60s to perhaps low 70s on Tuesday and Wednesday. Accordingly, although lows will be in the upper 50s to low 60s on Monday night, they look to trend warmer into the midweek, with the caveat that clear skies and diminishing winds overnight will promote ridge valley temperature splits that should keep valleys a few degrees cooler than NBM output would suggest. Cooling overnight will be accompanied by typical valley fog formation, particularly within mainstem river valleys.

Model spread increases significantly from Thursday onwards as shortwave energy moving through the base of a digging trough will attempt to suppress our pesky ridge. There is virtually no model agreement regarding how quickly the ridge begins to weaken, with some deterministic guidance showing the forecast area near the base of a trough by the end of the period, while other guidance keeps the ridge around seemingly indefinitely. Still, rain chances are favored to return near the end of the period as another cold front approaches.

AVIATION

(For the 12Z TAFS through 12Z Sunday morning) ISSUED AT 755 AM EDT SAT SEP 12 2026

A wavy front is now lifting north across the terminals this morning. Ahead of this, some low stratus and/or fog is resulting in patchy MVFR/IFR conditions. As the front passes, warm advection will increase resulting in deteriorating conditions from VFR/MVFR to MVFR/IFR as widespread showers and thunderstorms develop by afternoon. Confidence in timing/location of this convection was still too low to include with anything but PROB30 groups at specific TAF sites, though. Look for the convection to wind down later tonight, but that will probably just allow for areas of fog and low clouds to impact the airports. Winds will be light and variable through the bulk of the morning, trending south to southwesterly at less than 10 kts later as daytime heating commences behind the warm frontal passage. However, gusty and erratic winds will be possible within/near storms from late morning through the evening.

JKL WATCHES/WARNINGS/ADVISORIES

Flood Watch from noon EDT today through late tonight for KYZ044- 052-104-106-107-109-110-119-120.