991
FXUS63 KJKL 290315
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1115 PM EDT Tue Jul 28 2026

.KEY MESSAGES...

- Drier weather with modestly lower humidity behind a cold front
  will prevail from Wednesday through Friday.

&&

.UPDATE...
Issued at 1115 PM EDT TUE JUL 28 2026

Fog is apparent in derived satellite imagery in southeast KY,
concentrated in valleys which received rain. Have updated the
forecast for this trend, with fog expected to develop further
north and west overnight at least in the deeper valleys.

UPDATE Issued at 752 PM EDT TUE JUL 28 2026

At this point, only a few isolated showers remain near the TN and
VA borders. Won`t rule out a rogue lightning strike in the next
hour or so in that area, but the svr threat is done and svr tstm
watch 526 is gone from KY.

&&

.SHORT TERM...(This evening through Wednesday night)
Issued at 157 PM EDT TUE JUL 28 2026

Some showers and storms have developed across northern portions of
the CWA. Severe Thunderstorm Watch 526 is now in effect through 8 PM
this evening.

A closed low will deepen over Upstate New York this afternoon. The
systems cold front extends southwest through portions of
Pennsylvania, West Virgina, and Kentucky. After some morning
convection, the area has seen the sun peak out in spots. Surface
analysis and RAP guidance suggest MLCAPE will range between 2000-
2500 J/kg this afternoon, with 35-45 kts of effective bulk shear.
Storms are expected to develop along and ahead of this cold front
through the afternoon. The environment will favor supercell type
storms initially before transitioning into bowing segments. The main
hazard with these storms are damaging wind gusts. Model soundings
consistently show DCAPE around 1300 J/kg. With a dry mid layer
between 700-500 mb (lapse rate of 7.4C/KM), any rain that evaporates
passing through this layer, and cools could potentially aid in
accelerating downdrafts. With MUCAPE ranging between 3000-5000 J/kg
and DCAPE around 1300 J/kg the Derecho Composite tool on the SPC
page is cluing in on the wind potential. These showers and storms
should taper off by evening, with clearing skies behind the cold
front. Patchy areas of fog may develop overnight, with temperatures
cooling into the low to mid 60s.

Wednesday, high pressure slowly builds into the area Wednesday,
allowing for mostly sunny skies and highs in the lower 80s across
Eastern Kentucky. With light winds and clear skies Wednesday night,
patchy valley fog may develop in the late evening and overnight.
Temperatures will generally cool into the upper 50s to lower 60s.

.LONG TERM...(Thursday through Tuesday)
Issued at 437 PM EDT TUE JUL 28 2026

The long-term period opens Thursday morning with a deep trough axis
extending from Quebec southward to along the Mid-Atlantic and
Southeast US coast. Meanwhile, an ~596 dam high is in place over
the Southern Rockies with broader ridging across much of the
Central and Western CONUS. This leaves the Ohio Valley in a zone
of subsidence on the eastern side of the ridging, corresponding to
an area of surface high pressure. There is also a shortwave
trough riding over the top of the ridging across the Dakotas at
the start of the period.

Aside from some nighttime and morning fog in the typically favored
river valley locales, fair weather will be found across eastern
Kentucky through Friday as surface high pressure crests over and
just northeast of the JKL CWA. This will keep relatively cool
temperatures in place for both Thursday and Friday with highs in
the lower to mid 80s and lows in the mid 50s to near 60F. Dew
points falling into the upper 50s to lower 60s will make it feel
quite comfortable.

Looking ahead to the weekend and early next week, the shortwave
trough over the Northern Plains will dig southeastward and close
off into a low over the Mid-Mississippi Valley. A weak area of
surface low pressure will develop ahead of this feature over the
Central Plains on Thursday night into Friday, then occlude and
decay near or over the Commonwealth early next week. This system
will wrap higher humidity levels back into eastern Kentucky while
also bringing rounds of convection. As a result, daily high
temperatures will remain on the cool side, generally in the lower
to middle 80s, while nighttime lows moderate to between 65 and
70F.

&&

.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 752 PM EDT TUE JUL 28 2026

Only a few isolated showers remain near the TN and VA borders as
the period starts, and they will be gone soon. This will leave VFR
conditions to start the night. Fog will probably develop in the
deeper valleys later in the night. However, its spread with time
is uncertain due to advection of cooler/drier air into the area.
Have kept it out of TAFs for the time being. However, won`t rule
it out, with KSME and KLOZ being the most likely to be affected
should it spread from the deeper valleys. Where fog develops, IFR
or worse conditions may occur. Once fog dissipates on Wednesday
morning, VFR conditions are forecast through the day.

&&

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

&&

$$

UPDATE...HAL
SHORT TERM...GINNICK
LONG TERM...GEERTSON
AVIATION...HAL