795
FXUS63 KJKL 292025
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
425 PM EDT Tue Sep 29 2026

.KEY MESSAGES...

- Temperatures warm through Thursday, while humidity gradually
  increases through Friday and lingers this weekend.

- A slow moving boundary will likely bring showers and stray
  thunderstorms from Friday afternoon into the weekend until a
  secondary boundary passes to end the weekend.

&&

.SHORT TERM...(This evening through Wednesday night)
Issued at 410 PM EDT TUE SEP 29 2026

As of mid to late afternoon, the axis of an upper level ridge
extended from Mexico and the western Gulf across parts of the
Southern Plains/Arklatex to the mid MS Valley to Great Lakes to
Ontario and Quebec while an upper low and associated trough
extended from parts of Canada in the New Brunswick and Nova Scotia
area to the and the Northeast to Mid Atlantic coast. Further west
and northwest, a broad upper trough was moving across western
Canada to the Northern Rockies and an upper low was working across
the Southwest Conus. At the sfc, a ridge of high pressure
extended from the eastern Great Lakes to Appalachians. Skies have
been sunny today, and mixing has allowed for afternoon dewpoints
mainly in the upper 40s to mid 50s range. Temperatures moderated a
bit from previous days into the mid 70s to around 80 degree
range.

Tonight through Wednesday, guidance builds the upper ridge into
the Southeast Conus downstream of a broad upper trough from
Central Canada into the Northern Plains/High Plains and the upper
level low moving from the southwest Conus to NM. A general trend
of rising heights is anticipated across eastern KY. Also, a
shortwave trough in advance of the troughing to the west will trek
across the Great Lakes and parts of Ontario and Quebec. At the
same time, sfc high pressure is expected to remain from the
Appalachians to the eastern seaboard. On Wednesday night, the
axis of the ridge will shift to the east/southeast of eastern KY
while troughing moves into the Central Conus with the upper low
reaching the Southern Plains. Meanwhile, the sfc ridge remains
from the Southern to Central Appalachians to the coast of the
Carolinas. The pressure gradient will begin to increase late in
the period the frontal zone in advance of the troughing entering
the Central Conus.

The pattern will favor a continued warming trend and ridge/valley
temperature splits the next couple of nights, though the split is
likely to be a bit larger in magnitude for Wednesday night and
bit more confined to eastern and southeastern sections given the
increasing pressure gradient and some southerly breezes on ridges.
In the east and southeast, hollows and deeper valleys should more
readily decouple and remain decoupled. Fog should also be common
in the river valleys and along the larger creeks and lakes as has
been the case the past few nights. Tonight, there may be some
sections of patchy dense fog especially in the KY and Big Sandy
basins. Fog could be more limited in the western sections for
Wednesday night, with higher confidence for the east and
southeastern valleys.

.LONG TERM...(Thursday through Tuesday)
Issued at 340 PM EDT TUE SEP 29 2026

The extended period opens Thursday morning with a ~1020 mb surface
high over the Southeast beneath a building upper-level ridge. Further
upstream, an upper-level closed low (with central 500 mb heights
around 570-576 dam) embedded within a broader southern-stream trough
will be centered over the Southern Rockies and Southwest. Recent LREF
runs have trended noticeably more amplified with this pattern,
deepening the southwestern low while strengthening the ridge over the
Eastern US. This enhanced downstream ridge and strong southerly warm-
air advection (WAA) across the Ohio Valley account for the warming
pre-frontal temperatures in recent guidance, supporting highs across
Eastern Kentucky in the mid to upper 80s on Thursday and low to mid
80s on Friday.

An initial cold front will sink eastward toward the Commonwealth on
Friday, drawing rich Gulf moisture up the Mississippi and Ohio
Valleys and bringing an increasing coverage of showers and a few
embedded thunderstorms. As the southern-stream upper trough opens
up and the surface boundary stalls near the Ohio River/Appalachians,
shower and thunderstorm chances will linger across Eastern
Kentucky through Saturday. Temperatures will cool into the upper
60s to mid 70s on Saturday under persistent cloud cover and
intermittent rain.

A secondary northern-stream trough will dig into the Great Lakes and
Ohio Valley Sunday morning, pushing a reinforcing cold front through
the region and steadily lowering rain chances from northwest to
southeast through Sunday afternoon and evening (highs in the lower
70s). However, as the main trough axis slowly sweeps across the
Appalachians, isolated shower chances could remain along the KY-TN
and KY-VA borders through Monday morning. Drier continental high
pressure takes full control by Monday afternoon, shutting off any
remaining precipitation. While daytime temperatures remain pleasant
in the upper 60s to low 70s Monday and Tuesday, clear skies and light
winds Monday night will allow cooler lows in the 40s to return to the
area.

&&

.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 235 PM EDT TUE SEP 29 2026

Upper level ridging extending from the western Gulf into the
Appalachians and sfc high pressure centered east of the
Commonwealth will lead to mainly VFR conditions and light winds
through the period. The caveat will be valley fog between about
04Z and 14Z that may bring MVFR to localized IFR to VLIFR
conditions, though this is not expected to affect any TAF sites.
Outside of fog, VFR conditions will hold through the period along
with light winds.

&&

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

&&

$$

SHORT TERM...JP
LONG TERM...GINNICK
AVIATION...JP