textproduct: Jackson

KEY MESSAGES

- A well-defined, and rather strong, cold front will bring showers to most of the area tonight, and possibly gusty thunderstorms. - Some thunderstorms tonight may contain hail or damaging wind, especially near and north of Interstate 64.

- The airmass behind this front will be noticeably cooler and significantly drier. This could lead to critically low relative humidity values on Tuesday.

UPDATE

Issued at 915 PM EDT SUN MAR 22 2026

Late this evening, mainly just some passing high clouds were crossing the region at times in advance of a cold front that has moved a line from the WV panhandle to south of KILN to Cincinnati to southern IN to near Paducah. At present, showers and strong to severe storms linger behind the boundary from sections of IL across IN and OH. Mid level lapse rates in advance of the boundary are in the 7 to 8C/km range at present with this area of steeper mid level lapse rates of 7C/km or more progged to move across eastern KY over the next few hours. However, lower level moisture and BL moisture is quite lacking and MUCAPE across eastern KY is in the 200 to 500 J/kg range across the southeastern part of the area and nearer to 1000 J/kg north of I-64 and near Lake Cumberland. A good amount of CIN is analyzed and expected to persist as progged as the evening hours progress even as MLCAPE may reach the 500 to 1000 J/kg range briefly toward midnight. Effective shear is currently analyzed in the east and southeast at 25KT or less while effective shear is on the order of 35KT from areas north of I-64 to the Lake Cumberland vicinity. Effective shear is progged to climb to the 35 to 50KT range in the north through around midnight to the early predawn hours while low level lapse rates trend toward more marginal in the 5.5 to 6.5C/km range. If activity can develop nearer to the front toward midnight there could be a threat of generally sub severe hail and strong to damaging winds. Then with successive activity generally behind the front, in the overnight hail up to marginally severe levels could remain more of a threat than winds given the progged shear and MUCAPE values in the marginal to slight risk areas from SPC.

LONG TERM

(Tuesday through Sunday) Issued at 333 PM EDT SUN MAR 22 2026

The models are in good agreement with the long wave pattern remaining fairly amplified across the majority of North America through the end of the week. A seasonably strong ridge will start out positioned over the southwestern CONUS, while a closed low spirals off the coasts of British Columbia/Alaska and another over the Northwestern Passages. This will allow for brisk west to west northwest 500 mb flow across the northern half of the CONUS. Most of the better defined short wave energy will take a path closer to the Canadian border through the middle of next week, before some deeper northern stream energy inbound from south central Canada then traverses the Great Lakes/Ohio Valley region Friday into Saturday. By this weekend, a trough will be aligned across the eastern CONUS, while ridging aligns over the Continental Divide. By that time, there is more model disagreement regarding the amplitude and timing of these features.

A cool start across eastern Kentucky will be on tap Tuesday morning, with high pressure centered across the Upper Ohio Valley. During the day, a weak inverted surface trough noses in from the Tennessee Valley, with winds remaining light out of the east to east northeast for locations generally north of KY-80/Hal Rogers Parkway. Temperatures will rebound to the mid 50s north of I-64, to the mid 60s towards the Tennessee border. GFS/NAM MOS guidance has trended cooler with the highs this go around, but ECWMF MOS remains warm. The blended guidance remains on the warmer-side of guidance, and will continue this regime, especially given the amount of drier air noted in the 700-925 mb range. This may be one of those mornings when Black Mountain sees dew points go below or even well below zero at some point, as the associated subsidence inversion descends. There is still some uncertainty though on details, so have not deviated from the blended guidance much at this point. Did lower dew points a bit more so than the blended guidance indicated during the afternoon, but not quite as aggressive as the 10th percentile, given the more limited mixing expected. This will result in relative humidities bottoming out in the teens to 20s for most locations.

Surface high pressure will shift east Tuesday night, allowing for modest return flow. The dry start, despite an influx of potentially thicker high clouds should set the stage for some good deeper valley decoupling. Temperatures will dip into the mid to upper 30s at the typically colder hollows, while ridges stay up in the low to mid 40s. Winds will veer more to the southwest on Wednesday, allowing for increased moisture and warmer air. Highs rebound to the 60s and lower 70s, with plentiful low level clouds developing during the day. Clouds will continue into Wednesday night into Thursday morning, with a chance of showers and perhaps a rumble of thunder accompanying a passing warm front. Lows will moderate to the 50s. Thursday afternoon will be warm and dry, given the rising 500 mb heights. Highs will be in the upper 70s to lower 80s. A cold front will then approach from the northwest Thursday night and pass through eastern Kentucky on Friday, when PoPs currently peak in the likely range (50-70%). Depending on the exact timing, there could be quite a gradient in the high temperatures, with locations north of I-64 in the mid 50s, while early day highs in the lower 70s hang on nearest the Tennessee/Virginia borders. Drier weather will take hold for next weekend. Temperatures will dip into the 20s and 30s by Saturday morning, with below normal readings continuing through the day, as temperatures only rebound into the 50s for most locations. This coolness will be short-lived, as highs rebound to the 60s by Sunday, thanks to return flow ensuing once again.

AVIATION

(For the 00Z TAFS through 00Z Monday evening) ISSUED AT 830 PM EDT SUN MAR 22 2026

VFR conditions are forecast to begin the period. However, a cold front will move SSE through the area after the 03Z to 05Z timeframe, with showers and a few thunderstorms accompanying it. The boundary should reach the VA border by about 08-09Z. Widespread MVFR conditions are expected to arrive with the showers and any storms, with IFR possible for a few showers thereafter as well. Between 12Z and 18Z, IFR and MVFR should improve to or through the MVFR range to the VFR range from northwest to southeast. VFR conditions are expected areawide from about 18Z through the end of the period.

Initial gusty southwest winds should continue to diminish/subside after sunset, and for a few hours, result in a period of low level shear threat for all sites except KSYM. Winds will become more westerly as the front nears and then shift to the north and again gust at 15-20 KT after the cold frontal passage late tonight.

JKL WATCHES/WARNINGS/ADVISORIES

None.