FXUS63 KJKL 200728 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 328 AM EDT Wed May 20 2026 .KEY MESSAGES... - Shower and thunderstorms will become more prevalent today, with widespread rain chances continuing through the next seven days, including the holiday weekend. - The switch to an active and wetter pattern yields temperatures closer to normal readings, and is likely to provide at least temporary relief from drought conditions. && .SHORT TERM...(Today through Thursday) Issued at 328 AM EDT WED MAY 20 2026 A cold front will move southeast into eastern Kentucky this afternoon, then come to a stall later tonight through Thursday along the TN and VA borders. Meanwhile, broad forcing for ascent increases across the area through the day as a slow-moving shortwave approaches from the southwest, with the shortwave becoming gradually sheared out across southeastern Kentucky tonight into Thursday as shortwave ridging builds over the area by Thursday evening. As the front approaches from the northwest today and the aforementioned shortwave approaches from the southwest, rain chances will steadily increase. Current dew points in the 60s combined with a developing mid-level 30-40 kt speed max ahead of the shortwave will provide the kinematics and thermodynamics for scattered thunderstorms this afternoon, with low to moderate buoyancy from surface high temperatures forecast to reach the lower to mid 80s for much of the area, warmest in the Big Sandy Basin. Thus, a few isolated severe storms will be possible, with damaging winds and hail the primary severe threats. Additionally, downpours may cause localized high water issues in poor drainage areas. Showers and thunderstorm activity transitions to more of a shower/rain threat tonight into Thursday as the shortwave becomes sheared and the cold front stalls near or along the TN and VA state lines, creating more of an overrunning situation. The building upper ridging Thursday may allow for northwestern parts of the forecast area, especially toward the I-64 corridor and Bluegrass region, to stay mostly if not completely dry, as shower activity becomes more confined with time closer to the stalled front across southeastern Kentucky. Temperatures tonight will likely cool into the 50s, especially for northern areas behind the cold front, while lower to mid 60s for lows are expected toward the TN border to the south of the stalling front. Thursday's highs will be below normal for northern and central parts of the forecast area, likely around 70 degrees under persistent cloud cover and shower chances, with highs closer to normal near and south of the front near the TN and VA borders. .LONG TERM...(Thursday night through Tuesday) Issued at 302 AM EDT WED MAY 20 2026 The forecast period begins with the region likely situated north of a frontal zone Thursday night as a shortwave in southwest flow approaches the region. This should support the boundary lifting north as a warm front as a sfc wave rides into the OH Valley. With the northwest lifting warm front, it is probable that chances of convection will spread north through the overnight period Thursday night. Overnight lows are still expected to be mild as the warm front lifts north across the area. This warm front will cross the region on Friday, serving as the catalyst for widespread showers and scattered thunderstorms throughout the day as another wave moves along the boundary and treks toward the Great Lakes for Friday night. While marginal thermodynamic indices will once again favor pulse-type, non-severe convection, the primary hazard shifts toward heavy rainfall and high precipitation efficiency. This boundary likely remains north of the area to start the weekend, before sagging back into the OH Valley and stalling to end the period. Passing disturbances and the moist airmass, with PWs per the 12Z LREF generally in the 1.3 to 1.7 inch range, or the 90th percentile, should at least be conducive for a diurnal uptick in convection for Friday to Monday. The 12Z Tuesday LREF event totals through 8 PM EDT on Monday have a min to max range of 0.75 inches to near 7 inches, while the 25th to 75th percentile range from 1.5 or 1.75 inches near the VA border to 3.75 inches in the north and west. Recent deterministic guidance projects widespread QPF amounts ranging from 2.00 inches in the Lake Cumberland area to 2.75 inches across northeastern portions of the forecast area, with lesser amounts near 1.5 inches in southeastern KY near the West Virginia and Virginia borders, due to local downsloping effects. As a side note, since the area is dry, heavy rainfall on top of moisture starved ground could create runoff issues leading to potential hydrologic issues. Ultimately, this period will highlight a distinct regime shift toward a much wetter synoptic setup, a stark difference from the persistent dry pattern observed over the last few weeks and months. Due to persistent cloud cover and rain, daytime highs will remain capped in the upper 70s to mid 80s, while overnight lows drop into the lower to middle 60s. && .AVIATION...(For the 06Z TAFS through 06Z Thursday) ISSUED AT 143 AM EDT WED MAY 20 2026 Valley fog has developed in and around locations that saw rain during the afternoon and evening Tuesday, including at least briefly at KSME and KLOZ. This fog may continue intermittently through 09z-12z this morning, or until increasing lower cloud cover provides sufficient insolation to dissipate fog. Otherwise, the forecast features widespread VFR gradually diminishing to sub-VFR conditions as shower and thunderstorm activity increases through the morning and afternoon, with activity become more showery in nature after about 23z-02z, as the instability is mostly tapped out by that time as a weak cold front stalls from near KSJS to KJKL to north of KSME around 00z Thursday. Widespread MVFR or lower conditions are then likely after 00z as the front remains across the area and shower activity continues through the end of the TAF period. Thunderstorm activity will be most prevalent in the afternoon period, and a few storms could be on the strong side with gusty winds and hail. && .JKL WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...CMC LONG TERM...JP/VORST/CMC AVIATION...CMC