####018007010#### FXUS63 KJKL 062110 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 510 PM EDT Thu Aug 6 2026 .KEY MESSAGES... - The risk of showers and thunderstorms will persist for the next week, with the greatest coverage for the area as a whole on Friday-Saturday and Tuesday-Thursday. - Isolated heavy rainfall may occur where thunderstorms are most persistent through Saturday. && .UPDATE... Issued at 510 PM EDT THU AUG 6 2026 Near-term forecast grids were updated with the latest observational data across the area, blending recent trends into the T/Td fields. Additional edits were made to the PoP and Wx grids to account for shower and thunderstorm activity developing along a weak boundary across the Bluegrass region and adjacent areas to the east. No other changes were necessary for the near-term period. && .SHORT TERM...(This evening through Friday night) Issued at 357 PM EDT THU AUG 6 2026 A mostly to partly sunny early August afternoon is unfolding across eastern Kentucky with a few backyard-variety showers and thunderstorms, primarily over the higher terrain closer to TN and VA and over the Bluegrass. Temperatures range from the mid to upper 80s, while dew points in the low to mid 70s support heat indices in the 90s. The surface weather map is quite benign, with little discernible in the way of surface forcing features except for perhaps a subtle wind shift over the Bluegrass and central Kentucky. Convection further east is likely supported by differential heating over rugged terrain. The latest mesoanalysis shows 1,000 to 2,000 J/kg of MLCAPE but minimal shear - supportive of just ordinary pulse thunderstorms. Looking upstream, broad troughing extends across the northern tier of the CONUS from Montana to New England, reaching its trough base over the Mid- Mississippi Valley with an embedded 500 hPa vort max. Through the short-term period, the broad trough will slowly migrate eastward, with pieces of subtle vort energy crossing northern portions of the CWA later tonight and Friday. The most substantial of those vort maxes, situated in the base of the trough, will approach the JKL CWA from the west late Friday night. Ongoing convection will remain strongly diurnally modulated and pulsey this evening, dissipating with the loss of diurnal heating and lack of other forcing. A stray shower or rumble of thunder cannot be entirely ruled out late tonight, as modest elevated instability remains while the first subtle vort perturbation skirts the I-64 corridor. On Friday, convection is favored to redevelop over the southeastern high terrain near the VA/KY border thanks to differential heating. Meanwhile, a second subtle perturbation passing near/north of the Lower Ohio River could spark additional convection, especially near and north of the I-64 corridor. There will be a better chance for at least isolated to scattered convection persisting through Friday night as the third and most substantive vort max of the period approaches with the 500 hPa trough axis. Similar to recent days, we will remain under a weak shear and moderate CAPE environment with seasonably high PWATs, slow storm motion, and weak Corfidi upshear vectors, so there is at least some risk for locally heavy rainfall. Accordingly, WPC has maintained a Marginal Risk ERO for the entire short-term period. Also, while a gusty shower or storm cannot be ruled out today, the parameter space will be slightly more favorable for downburst winds Friday afternoon near and north of the I-64 corridor, where DCAPE and 0-3 km Theta-E difference values will be marginally favorable for stronger downdrafts in an environment with EBWD strong enough to support some multicell organization. In sensible weather terms, look for seasonably warm and humid August conditions to continue, with highs in the mid 80s for most while nighttime lows dip into the mid 60s to around 70F. Showers and thunderstorms will follow a diurnal cycle, with greatest coverage in the afternoon and evening and least overnight into early morning. Any isolated to scattered activity this evening will tend to be more focused along the I-64 corridor and near the VA/KY border, with lesser coverage in between. Aside from a rogue shower or storm, it should be mostly dry overnight and early Friday morning, with fog once again probable through the river valleys. Additional shower and thunderstorm development can be expected Friday afternoon and evening, again most numerous near the KY/VA border and near the I-64 corridor. Storms in the north Friday afternoon have a better chance of producing gusty winds. Convection then diminishes again Friday night with the loss of daytime heating, though isolated to scattered activity will still be possible. .LONG TERM...(After midnight Friday night through Wednesday) Issued at 810 AM EDT THU AUG 6 2026 A lobe rotating around a large upper low over Hudson Bay will extend a trough southward over the Ohio Valley at the start of the period. This will reach southward into a col between upper highs over the southwest CONUS and off the southeast coast. This weakness in the subtropical ridging will allow for at least scattered showers/thunderstorms for our area as we move into the weekend. The troughing retreats northward by Sunday and rising geopotential heights should result in less convection through Monday. A series of shortwave troughs then nudge the prevailing westerlies aloft southward again by mid week and give us slightly increased west northwest flow aloft. This regime gives an increased potential for showers/thunderstorms with a risk of MCS occurrence Tuesday-Wednesday. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) ISSUED AT 215 PM EDT THU AUG 6 2026 Primarily low-end VFR was present at TAF issuance under a scattered to broken cumulus field. Still anticipate isolated to scattered showers and thunderstorms to develop later this afternoon and persist into this evening, bringing localized sub- VFR conditions. The greatest confidence in shower impacts are at those sites near the KY-VA border, KY-TN border and along the I-64 corridor. Most of the precipitation should die out this evening, but valley fog should develop to some extent once again during the night. The fog's extent is uncertain, and may be more restricted if there is more cloud cover as compared to the preceding night. Winds will generally be southwesterly at less than 10 kts. However, locally gustier and erratic winds will be possible near any thunderstorm. && .JKL WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...GINNICK SHORT TERM...GEERTSON LONG TERM...HAL AVIATION...GEERTSON/HAL