textproduct: Jackson

KEY MESSAGES

- Light snow accumulations are possible behind a cold frontal passage on Sunday Night/Monday Morning.

- Southwesterly winds will become gusty on Tuesday and Wednesday ahead of a stronger mid-week system.

- The pattern remains active next week, although confidence remains low in each passing system's precipitation type forecast.

UPDATE

Issued at 759 AM EST SAT DEC 6 2025

A break in the low clouds has developed over the center of the CWA around sunrise, but another disturbance is approaching from the northwest with additional cloud cover. The cloudier skies will generally be more predominant today with northward extent while sunshine will be more prevalent near the VA/KY and TN/KY borders.

LONG TERM

(After midnight Sunday night through Friday) Issued at 609 AM EST Sat Dec 6 2025

The long term forecast period opens with the passage of a cold front on Sunday night, and the resultant cold air advection regime will allow ongoing precipitation to mix with and then change over to all snow by Monday morning. The arrival of this boundary's parent midlevel shortwave disturbance has trended slower in recent forecast guidance, leading to prolonged precipitation chances in far Eastern Kentucky. Precipitation is generally expected to taper off from NW to SE during the daytime hours on Monday, but will linger into the afternoon for locations south of I-64 and east of I-75. The probability of measurable snowfall in the JKL CWA has accordingly increased, with the LREF Grand Ensemble now depicting a 50-70% chance of seeing at least 0.1 inches of storm total snowfall across much of the forecast area on Monday evening. The LREF probabilties continue to drop off quickly with increasing accumulation thresholds, but some higher-resolution pieces of guidance suggest that locally higher totals in higher-elevation locations closer the Virginia state line cannot be ruled out. For example, the 00z ECMWF AIFS Ensemble Probabilities for >= 1 inch of snow jumped to 20-30% in places east of the KY-15 corridor, and the higher-resolution 00z/06z deterministic NAM runs include terrain enhanced totals in out southeasternmost counties. As this early-week system enters the temporal range of other pieces of higher resolution forecast guidance, trends in these probabilities will need to be monitored. The mention of light snow accumulations on Sunday night/Monday morning was accordingly retained in this morning's Hazardous Weather Outlook, but antecedent warmth during the daytime hours on Sunday and a quick-building shortwave ridge will likely serve as limiting factors.

Models collectively resolve midlevel height rises on Monday night into Tuesday as a ridge briefly builds into the Ohio River Valley. At this surface, this translates to a quick-passing high pressure system, and a clearing trend looks likely overnight. This could lead to ridge-valley temperature splits on Tuesday morning. While temperatures are forecast to be well below freezing area-wide, shaded/sheltered valleys could drop into the teens while ridgetops stay in the mid-20s. Locally colder thermometer readings are also possible wherever there is snow on the ground, but once the sun rises, temperatures are forecast to quickly moderate above freezing. The surface high will propagate east of the area by midday and set up a potent warm air advection regime. Breezy southwesterly winds and relatively sunnier skies will allow for widespread afternoon highs in the 40s, and clouds should begin to spread back into the forecast area on Tuesday night. These clouds, coupled with the persistence of southwesterly low level flow, will limit the amount of diurnal cooling on Tuesday night. Thus, most of the area is poised to remain above freezing ahead of the next system's arrival on Wednesday.

As that mid-week system approaches the area, a tightening pressure gradient will allow the persistent southwesterly surface flow to intensify. Confidence is growing that Wednesday will be a rather windy day. Models depict strengthening flow aloft in this same time frame, and BUFKIT momentum transfer soundings continue to depict wind gusts in the range of 30-35 knots at the sample sites across our forecast area. The latest EPS ensemble data suggests that there is a 25-40% chance of exceeding wind advisory criteria (40 mph) on Wednesday. Winds of this magnitude are likely to blow around any outdoor holiday decorations, and these nuisance-type impacts are poised to be the primary concern with this mid-week system. WAA will allow temperatures to climb into the upper 40s/lower 50s by Wednesday afternoon, meaning that rain would be this system's favored precipitation type.

After the onset of this rain on Wednesday afternoon, forecast confidence decreases. There is a strong signal for active weather to continue through the end of the forecast period, as a train of clipper-type systems is likely to approach the Greater Ohio River Valley late next week. The track, timing, and evolution of each individual disturbance in this procession remains highly uncertain, which makes it difficult to pinpoint specific details regarding temperature profiles, precipitation types, and potential accumulations. The baseline NBM guidance used to populate the long term grids averages out into liquid precipitation types during the day and frozen precipitation during the cooler nights, but the actual p-type forecast will be dependent upon the speed and depth of each passing system's parent trough. It is plausible that a quick- moving system on the heels of its predecessor's cold air advection could lead to more widespread winter weather, but it is also plausible for a brief period of WAA to set up between systems. Better-defined long wave troughing looks to eventually set up over the Eastern CONUS just beyond the end of the period, so a general downward trend in temperatures is expected towards the very end of the period. Nevertheless, interests are encouraged not to read too far into deterministic winter precipitation accumulation data at this moment in time, as it is likely to be quite bouncy.

AVIATION

(For the 12Z TAFS through 12Z Sunday morning) ISSUED AT 717 AM EST SAT DEC 6 2025

Patchy low ceilings (MVFR or worse) with some breaks lingered at TAF issuance. These clouds will persist through much of the morning at the terminals as a weak disturbance passes. Ceilings should then gradually break up more substantially this afternoon and evening, yielding a period of VFR conditions as high pressure brushes to our south. Winds will become southwest at 4 to 9 knots by late this morning/early afternoon.

JKL WATCHES/WARNINGS/ADVISORIES

None.