824
FXUS63 KJKL 200854
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
454 AM EDT Sun Sep 20 2026

.KEY MESSAGES...

- Unseasonably hot and muggy weather continues through Monday,
  with near-record high temperatures reaching the upper 80s to
  lower 90s in most places today.

- Strong to severe thunderstorms with damaging wind gusts are
  possible Monday afternoon and evening, mainly south of the
  Mountain Parkway.

- A stalled front brings widespread showers and thunderstorms
  Monday night through Wednesday, with isolated flash flooding
  possible from repeated heavy downpours.

- Seasonably cooler and drier air arrives Thursday and persists
  through the weekend, with daytime highs in the 70s and
  nighttime lows in the 50s, except in the upper 40s for some
  cooler valleys.

&&

.SHORT TERM...(Today through Monday)
Issued at 443 AM EDT SUN SEP 20 2026

Our stretch of unseasonably warm weather has an end in sight just
beyond the end of the short-term period. In the interim, we will
see two more hot and muggy days with at least some opportunities
for passing showers and thunderstorms. Presently though, all is
quiet across eastern Kentucky this morning, with just patchy mid-
level cloud cover, fog in sheltered valley locations, and
temperatures ranging from the mid 60s to mid 70s. Regional radar
imagery shows an extensive cluster of thunderstorms to our north
over southern Ohio and parts of West Virginia. More extensive
convection is noted from northern Indiana and Illinois back to the
southwest through Kansas. The latest surface analysis shows this
activity near a wavy frontal boundary extending from Pennsylvania
westward to a weak surface low over central Illinois. A cold
front extends southwestward from the low into Kansas and Oklahoma.
Looking aloft, the upper-level high of recent days has weakened
to 591 dam, but remains centered over the Ark-La-Tex, leaving
eastern Kentucky along its northeastern periphery. Meanwhile, a
500 hPa trough, with an embedded 575 dam closed low over central
Wyoming, is passing over the Great Basin and central Rockies.

The upper-level ridge will continue to weaken through the duration
of the short-term period, allowing heights to slowly fall over
eastern Kentucky and leading to a more quasi-zonal flow under
mid-latitude westerlies by late in the day on Monday. Most of the
upper-level vort energy ejecting out of the upstream trough will
ride around eastern Kentucky today, but by Monday, the favored
corridor for that energy will begin to more directly impact the
Commonwealth. Consequently, minimal forcing should leave today as
the drier of the two days. That being said, some convection cannot
be ruled out this morning over northeastern Kentucky along outflow
generated by ongoing shower and thunderstorm activity over
southern Ohio and West Virginia. Otherwise, pulse/multicell
convection could bubble up this afternoon and evening with
differential heating and orographic effects, but should stay
isolated to scattered given the lack of better forcing.
Today`s peak instability will be modest, with MLCAPE values of
1000 to 2000 J/kg, but around 1000 J/kg of DCAPE could be enough
for a few stronger wind gusts. The aforementioned boundary will
sink to near the I-64 corridor tonight and keep the possibility of
isolated convection in the forecast overnight. That front then
makes a slow push southward Monday afternoon into a hot and humid
air mass over southeastern Kentucky. Model soundings support
better instability (MLCAPE values of 1500 to 3000 J/kg) in tandem
with better shear (20 to 25 kts of EBWD), still-elevated DCAPE
values, and steep low-level lapse rates. This does appear to be a
favorable setup for isolated to scattered strong to severe
thunderstorms, with damaging wind gusts as the primary hazard from
collapsing water-loaded updrafts. While elevated PWATs are
supportive of heavy downpours, fairly dry antecedent conditions
should be a significant mitigating factor as far as flooding is
concerned.

In sensible weather terms, look for morning valley fog to lift and
yield to partly to mostly sunny skies today. A few isolated to
widely scattered showers and thunderstorms (10 to 30 percent
chance) cannot be ruled out, but most locations should be dry. It
will still be hot and humid, with high temperatures nearing record
levels in the upper 80s to lower 90s. Some of the hottest places
near Lake Cumberland could flirt with the mid 90s. Partly cloudy
skies follow for tonight, with renewed fog in favored valley
locales and low temperatures dipping back into the mid 60s to
lower 70s. A rogue shower or storm cannot be completely ruled out.
Looking ahead to Monday, it will again be unseasonably warm, with
highs in the lower 80s far north to lower 90s over the Cumberland
River Basin. There will be a better chance for showers and
thunderstorms by afternoon (40 to 60 percent chance), the
strongest of which could be severe with damaging wind gusts. The
highest chance for severe weather will be south of the Mountain
Parkway.

.LONG TERM...(Monday night through Saturday)
Issued at 443 AM EDT SUN SEP 20 2026

The extended period opens Monday evening with fairly zonal flow
aloft. At the surface, a strong area of high pressure will be
situated south of James Bay. South of this high, a cold front
will be draped from the Mid-Atlantic across the Commonwealth,
trapped between the high pressure to the north and parallel upper-
level steering winds. The result: showers and thunderstorms will
likely be ongoing Monday evening.

Farther west, an upper-level shortwave and broad troughing west of
the Great Lakes will slowly translate eastward toward the Upper
Midwest and Mississippi Valley. Quasi-zonal flow ahead of the
shortwave, coupled with multiple perturbations riding along the
stalled front, will allow for numerous to widespread showers and
isolated to scattered thunderstorms through Wednesday. WPC has
placed portions of the CWA in a Marginal Risk (Level 1 of 4) ERO
Tuesday and Wednesday due to some potential for excessive
rainfall. Areas that experience repeated rounds of storms could
see isolated instances of flash flooding.

On Thursday, amplification and passage of the upper-level trough
should bring an end to the prolonged wet pattern. As the trough
axis moves east of the area, drying of column will rapidly lower
PWATs and bring drier conditions through the rest of the week and
into the weekend. However, given timing discrepancies in model and
ensemble guidance, lingering showers cannot be ruled out across
the Big Sandy as well as eastern portions of the Kentucky River
and Upper Cumberland River basins on Thursday. Otherwise,
seasonably cool weather takes hold: daytime highs in the 70s and
nighttime lows in the 50s return from Wednesday night onward, with
some cooler valleys potentially dipping into the upper 40s.

&&

.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 145 AM EDT SUN SEP 20 2026

Primarily VFR conditions were found across the JKL forecast area
at the 06Z TAF issuance -- the only exception being the most
sheltered river valleys where some fog has formed. There is a
small chance that a shower or storm could affect SYM or SJS toward
daybreak as convection over Ohio drifts south and east but
confidence was too low to mention in the TAFs at this point.
Otherwise,the river valley fog will dissipate on Sunday morning,
leaving generally VFR conditions area wide through the afternoon.
The only exception to that would be an isolated shower or
thunderstorm risk. Winds will generally be light and variable
through daybreak then become southwesterly 3 to 7 kts by
afternoon

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...GEERTSON
LONG TERM...GINNICK/GEERTSON
AVIATION...GEERTSON