textproduct: Jackson

KEY MESSAGES

- Spotty light precipitation will wind down in the southeastern counties early this evening.

- 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.

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 18Z TAFS through 18Z Wednesday afternoon) ISSUED AT 107 PM EST TUE DEC 2 2025

A mixture of IFR and MVFR was reported at issuance with upslope flow between a departing area of low pressure and high pressure gradually building in from the central Conus. Spotty light precipitation likely a mixture of snow, drizzle, and perhaps spotty freezing drizzle lingers south of the TAF sites. That precipitation should end over the first 2 to 5 hours of the period, but low level moisture will linger for much of the period and if and or when any clearing does take place, fog with some IFR reductions may develop. In addition, as the night progresses, some stratus build down fog with IFR or lower vis is also possible for KJKL, KSJS, KSME, and KLOZ. Otherwise, mainly a mixture of MVFR and IFR ceilings are anticipated areawide through about 09Z, before high pressure building in leads to some scattering of low clouds from that point through the end of the period.

Winds will average northwest at 5 to 10KT to begin the period an then become light and variable after 23Z.

JKL WATCHES/WARNINGS/ADVISORIES

None.