textproduct: Jackson

KEY MESSAGES

- Drier and colder weather will be in place for the middle of the week. Temperatures will average between 5 and 10 degrees colder than normal.

- Light snow is possible Thursday night into Friday morning before any precipitation changes to rain.

- The pattern will turn active again towards the weekend with additional chances of precipitation.

UPDATE

Issued at 1145 PM EST TUE DEC 2 2025

Not a lot of change to the forecast. Did make minor updates to Sky and low PoPs through the remainder of the night for continued flurry potential. Otherwise, the latest hourly observations were used to initialize the hourly forecast grids.

UPDATE Issued at 842 PM EST TUE DEC 2 2025

Extensive low stratus deck continues with northwesterly low-level upslope flow helping to squeeze out flurries and light snow showers. Have upped PoPs to account for this, utilizing the CAMS as the starting point, especially the NAMNest, which tends to be one of the better models in this post-frontal northwesterly upslope flow regimes. Any snow accumulations will be no more than a dusting at any one location.

UPDATE Issued at 548 PM EST TUE DEC 2 2025

Raised overnight low temperatures a couple of degrees as extensive low clouds and moisture should keep temperatures from falling as much as what the NBM has predicted. Nevertheless, it will still be a cold sub-freezing night across eastern Kentucky. Also added a bit more fog for the ridges where the low clouds may intersect the tops of the plateau across the area.

Taking a quick look at the forecast for Wednesday, there are suspicions that extensive low clouds will linger longer through the daytime hours than currently forecast, which would have a detrimental effect on the forecast high temperatures, especially across the northern and central parts of the forecast area.

LONG TERM

(Thursday through Tuesday) Issued at 241 PM EST TUE DEC 2 2025

The forecast period commences with surface high-pressure dominance, yet aloft, two distinct synoptic-scale waves are poised to govern the weather through the initial segment of the forecast. The first is a minor shortwave trough currently ejecting from the Great Lakes, which is expected to have negligible impact on the forecast area. The more significant feature is a potent upper-level trough moving eastward from the Rocky Mountains at the start of the period.

This feature is forecast to track swiftly eastward along the Red River Valley through Thursday before lifting northeastward into the Tennessee Valley by Friday morning. As this trough lifts, the precipitation shield will encroach from the south, beginning as all snow but rapidly transitioning to a wintry mix as the elevated warm layer advects northward. Both the GEPS and GEFS ensemble probabilities indicate the highest threat for freezing rain over Tennessee, with approximately a 10% chance across the southernmost tier of counties in the forecast area. Nevertheless, as the surface cyclones warm front progresses northward throughout the day, the wintry precipitation will transition to predominantly rain before the system departs the region by late Saturday morning. A brief period of a wintry mix remains possible on the backside of the departing system as cold-air advection returns to the region.

Model confidence begins to degrade heading into the remainder of the weekend. Some agreement exists between the ECMWF and GFS models, but the ECMWF favors a quasi-zonal flow pattern through the weekend ahead of another shortwave, whereas the GFS accelerates another fast- moving shortwave with the CWA remaining under a southwesterly flow regime through the duration of the weekend. Long-term guidance returns to better continuity with the development of the latter shortwave. At the surface, this translates to the return of surface high-pressure for the weekend, but increasing PoP is expected late Sunday afternoon with the approach of the trough. This system appears likely to bring another round of wintry mix, as critical thickness contours, forecast soundings, and ensemble probabilities suggest the CWA could experience the full spectrum of winter precipitation types through the conclusion of the forecast period.

The overall period will be punctuated by intervals of surface high pressure interspersed with episodes of rain and wintry mix. Temperatures are forecast to remain slightly below average throughout the period.

AVIATION

(For the 06Z TAFS through 06Z Thursday) ISSUED AT 1143 PM EST TUE DEC 2 2025

MVFR/IFR cigs will persist with low stratus continuing through 12z, but cigs will begin to improve after 12z through the daytime hours as southwest winds begin to increase just above the surface. If and/or when any clearing does take place overnight, fog with some IFR or lower reductions may develop, but this is lower confidence. Light and variable winds are expected through the period.

JKL WATCHES/WARNINGS/ADVISORIES

None.