706
FXUS63 KJKL 222011
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
411 PM EDT Wed Jul 22 2026

.KEY MESSAGES...

- Mainly dry weather is expected from tonight to Friday, with
  temperatures averaging about 5 degrees below normal.

- Unsettled weather is forecast to return this weekend with
  temperatures warming to near normal by early next week.

&&

.SHORT TERM...(This evening through Thursday night)
Issued at 350 PM EDT WED JUL 22 2026

The afternoon surface analysis indicates a weakening boundary
continue sag southward across Kentucky. This feature will continue
slide southward through the remainder of the afternoon into the
evening and generally stall out across the Tennessee Valley, as high
pressure moves into the Ohio Valley. Ahead of the front this
afternoon we are seeing a few mainly isolated showers develop, but
these have been quite weak. We are starting to see much drier air
work into the region. The question tonight is how much fog do we see
given the high pressure and mostly clear skies. However, there is
some concern we will see enough mixing to minimize development and
therefore have remained close to previous forecast of more river
valley fog. This airmass will aid in dropping lows into the low to
mid 50s in the valleys and mid to upper 50s on the ridges. These
lows will the closer to average low temperatures we see in
May/June across eastern Kentucky.

High pressure will keep the weather quiet for the short term period,
with a dry and relatively cool day in store for Thursday. Again, the
afternoon highs are closer to normals for the end of May into
early June and closing in on 10 degrees below normal for this
time of year in some spots. The airmass will also be noticeably
drier, with afternoon dewpoints mixing into the low 50s to around
60 degrees. This is leading to sub 1 inch PWATs which is quite a
refreshing airmass for this time of year. This leads to another
decent ridge/valley temperature split night, with valleys dropping
into the low to mid 50s and ridges in the mid to upper 50s.
Again, expect some mainly river valley fog to setup once again.

.LONG TERM...(Friday through Wednesday)
Issued at 410 PM EDT WED JUL 22 2026

The long term period will be characterized by upper level ridging
over the western CONUS and an upper level trough over the
northeastern CONUS, with anomalously high 500 mb heights over much
of the central and western CONUS. Locally, eastern Kentucky will
find itself in a region of northwest flow aloft for nearly the
entire duration of the long term as the Commonwealth becomes
sandwiched between these upper level features. This will allow for
multiple shortwaves to rotate through the forecast area, bringing
additional chances for rain throughout the forecast period.

On Friday, an approaching shortwave will allow for modest height
falls across the Ohio Valley, with surface troughing in the vicinity
of the KY/VA line. Concurrently, surface winds will shift to be more
northwesterly to westerly, ushering in a period of moisture
advection. By Friday afternoon, dewpoints will rise into the low to
mid 60s in the northwestern half of the forecast area, and into the
upper 60s to perhaps low 70s in the southeastern portion of the
forecast area. With northwesterly flow through much of the column,
precipitable water will still remain below average in the northern
portion of our forecast area; however, moisture quality will be
better farther south, which will allow for some isolated showers and
perhaps a rumble of thunder close to the VA state line. Elsewhere,
weather is expected to remain dry, although rain chances will
increase somewhat in the southern portion of the forecast area
overnight as an additional shortwave approaches, with the best
chance for rain still near the KY/TN line. Rain chances remain
lowest in our northern counties, where the air mass will be
marginally drier. Here, skies may remain clear enough to allow for
just enough radiative cooling to set up a mild ridge/valley
temperature split; however, this remains dependent on the magnitude
of cloud cover overnight. Rain chances remain in the forecast
through the weekend, primarily for the southern half of the area as
additional impulses traverse the Commonwealth; however, uncertainty
in the timing of these features still remains high.

We begin to see more ridge riding impulses that move in from the
northwest, as we get stuck in between the strengthening ridging to
the west and troughing in the east as mentioned above. This leaves
the Ohio Valley in a locally semi-zonal northwest flow pattern, as
we move into the first part of the work week. There does remain some
timing uncertainty with these impulses and this leads to more
uncertainty in the forecast through the middle of next week. There
are some decent signals showing up in the deterministic and ensemble
data that would suggest the potential for stronger storms, with
signals for increasing effective shear and CAPE profiles. This is
showing up well in the ECMWF extreme forecast index with increasing
signal for higher values climatologically for the combination of
CAPE/shear. The signals are the strongest in the machine learning
the AI products as we get into the Monday and Tuesday timeframe. SPC
does mention some signal showing up in the Ohio Valley, but still
enough uncertainty to forgo any highlighted areas in the days 4-8
outlook period. This will have to be watched closely for future
outlooks and updates in the NWP.

&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 139 PM EDT WED JUL 22 2026

A cold front will continue to progress across eastern Kentucky
this afternoon into the evening. The good news is we are not
seeing VFR at all the TAF sites, but we are seeing cloud streets
of cumulus that are around the MVFR level. The TAF sites should
mostly remain VFR through the period. However, we will see at
least some potential for valley fog tonight. The question tonight
is how mixed we remain, and the forecast soundings suggest a
decent amount of mixing. This leads to a fair amount of
uncertainty for fog development, but opted to retain the MVFR
range mist for the TAF sites. The winds will remain VRB less than
5 knots in most cases, but some of our more exposed sites will
see wind registering out of the north and west.

&&

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

&&

$$

SHORT TERM...DJ
LONG TERM...DJ/FAGAN
AVIATION...DJ