Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

724
FXUS63 KJKL 301120 AAA
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
720 AM EDT Thu Apr 30 2026

.KEY MESSAGES...

- Cool and mainly dry weather will prevail through the weekend,
  with frost possible around dawn on Sunday.

- The next area-wide potential for showers and thunderstorms will
  be Monday through Wednesday.

&&

.UPDATE...
Issued at 700 AM EDT THU APR 30 2026

It appears that the fog has mostly dissipated with some northwest
wind flow and thicker clouds in the southeast. Therefore have
updated the forecast to take out the fog. Otherwise, no
significant changes were made to the forecast with mainly just the
inclusion of the latest obs and trends for the T/Td/Sky grids.
These minor adjustments have been sent to the NDFD and web servers
along with a freshening of the HWO, SAFs, and zones.

&&

.SHORT TERM...(Today through Friday)
Issued at 420 AM EDT THU APR 30 2026

08Z sfc analysis shows cool and dry high pressure moving into
Kentucky from the west. Before it gets here effectively, though,
plenty of clouds are moving through southeast Kentucky with some
sprinkles in the south and areas of valley fog lingering ahead of
the lower RH arriving. Specifically, amid northwest winds of
around 5 mph, dewpoints vary from the mid 40s west to the lower
50s in the far southeast. Meanwhile, temperatures range from near
50 degrees in the northwest to the mid 50s in the southeast.

The models, and their individual ensemble suites, continue to be
in great agreement aloft through the short term portion of the
forecast. They all depict deep 5h troughing over the Great Lakes
and extended through the Ohio Valley to start the period. This
negative anomaly will be the driver for our weather through the
rest of the week and into the weekend. South of the trough, fast
and nearly zonal mid-level flow will cross Kentucky pushing
another wave of energy through the JKL CWA this morning. After a
lull, the next node and shortwave of the parent trough swings
this way late tonight while the mid-level flow briefly tilts more
northwesterly. Some minor 5h height falls push into this part of
the state on Friday with this wave. Given the terrific agreement
among the models, the NBM was used as the starting point for the
grids. The main adjustments made to this initialization were to
include additional terrain details in the hourly temperatures
tonight.

Sensible weather features some sprinkles passing through the
southern parts of the area pre-dawn while patchy fog will be found
in the valleys and likely locally dense. The fog and mid-level
clouds clear out fairly fast this morning as that high pressure
pushes into the area more effectively. The drier air and sunshine
will help cool temperatures rebound from the morning lows, but
still only reach the upper 50s and lower 60s by late afternoon.
For tonight, initial clear skies, drier dewpoints, and light
winds will allow for decent radiational cooling before the next
band of clouds move in from the northwest. These clouds may
disrupt the fog fog depth late tonight, but a good amount will
still set up after midnight, especially in the valley and likely
become locally dense. We will also see valley temperatures get
close to, or just dip into, the upper 30s, but we are not
expecting much of a risk for frost until later in the weekend. A
weak wave of low pressure will then pass to the northeast by
midday Friday - supported by that upper level trough node as it
swings by. Consequently, there will be a small chance for a
shower or two sneaking past in the northeast part of the JKL CWA
through early afternoon. Even so, look for temperatures a bit
warmer to end the work week - compared to those of today.

The changes to the NBM starting point mainly consisted of tweaking
the hourly temperatures for some terrain distinctions tonight. As
for PoPs, did localize the slight chances in the south early this
morning and incorporate some CAMs guidance into the NBM`s threat
of showers on Friday.

.LONG TERM...(Friday night through Wednesday)
Issued at 300 AM EDT THU APR 30 2026

The forecast guidance suite remains in generally good agreement with
the synoptic weather pattern during the long term forecast period.
Broad troughing is expected to remain in place over the Eastern
CONUS through early next week, and a series of embedded shortwave
disturbances will navigate around it. Such a pattern favors below-
normal temperatures, and the primary weather concern during the
period looks to be the potential for an early May frost this
weekend.

A frontal passage associated with the first of those shortwaves will
shift low level flow to a more northerly orientation at the start of
the period on Friday night. That wind shift allows a cooler and
drier airmass to move into Eastern Kentucky for the weekend. Expect
overnight lows to follow a NW to SE gradient on Friday night. Our
northwestern locales in the Bluegrass region could experience lows
in the upper 30s due to an earlier frontal passage and thus a longer
residence time within the cool northerly flow. Southeastern portions
of the CWA will retain a westerly wind component and thicker cloud
coverage for longer on Friday evening, resulting in lows in the 40s.
Lingering moisture/clouds will likely preclude the development of
frost on Friday night, but a reinforcing shot of cold air arrives on
Saturday.

The second midlevel perturbation clears the area on Saturday
afternoon/evening and yields deeper north-northwesterly flow. As a
result, cold/dry air advection is poised to intensify with the
passage of Saturday`s wave. The dry nature of the resultant
continental airmass will play a large role in the sensible weather
forecast. The NBM continues to resolve low-end (<=25% PoPs) across
portions of the forecast area on Saturday afternoon as this next
wave approaches. While it is true that Saturday`s wave is better-
defined and deeper than Friday`s, any resultant precipitation will
have to pass through a more pronounced layer of low-level dry air.
Dewpoints are forecast to drop down into the lower 30s across the
entire forecast area on Saturday afternoon, which could cause that
precipitation to be realized as virga. Furthermore, the continued
signal for a deeper trough suggests that the related surface low
will remain displaced well to the SE of the forecast area. The Gulf-
Atlantic coast low pressure track is favored in this kind of set up,
and this would keep the majority of precipitation displaced to the
other side of the VA/TN state line. Given all of the above, a
clearing trend is favored headed into Saturday night, and valley
locales should subsequently cool to near the freezing mark.

Confidence in frost formation on Saturday night remains highest in
the most sheltered/shaded valleys and hollows of Eastern Kentucky.
Widespread frost wording has been limited to these cooler locations,
and this generally corresponds to where the driest dewpoints are
forecast on Saturday afternoon. In the wider valleys and in the more
exposed locales of the Bluegrass, areal frost wording was adopted.
Patchier frost is plausible elsewhere, and those with frost-
sensitive interests (such as recreational gardeners and agricultural
crop producers) should review any necessary protective actions ahead
of time. The tallest ridgetops may avoid a frost by staying closer
to 40 degrees, but models resolve the 540 dam critical thickness
contour in the vicinity of the forecast area by 12z on Sunday
morning. This gives credence to the notion that the airmass in place
across the commonwealth on Saturday night is much below
climatological normals. Thank goodness that it is also a drier
airmass, as otherwise, we might be discussing the potential for
wintery precipitation during the first weekend of May.

The progressive nature of the overarching pattern means that the
forecast remains active in the early stages of next week. There is
increasing model spread with regard to the timing of the next
approaching trough and its associated surface features, but expect
temperatures and atmospheric moisture content to increase through
midweek. The surface high responsible for Sunday`s pleasant and
mostly clear conditions shifts east into the Carolinas by Monday
afternoon. This will back winds towards the southwest, yielding WAA
and highs back in the 70s. Dewpoints will be slower to recover, but
as the next midlevel trough approaches, that southwesterly flow
deepens and steadily pumps dewpoints towards the upper 50s/lower
60s. Expect shower and thunderstorm chances to increase in
accordance with this trend, with the most widespread chances
currently coming on Wednesday. Isolated to scattered activity cannot
be ruled out before then, but widespread strong to severe storms are
not currently anticipated. Rather, this activity will work to
provide highly beneficial rainfall across the region, as we remain
below annual averages as of the time of writing.

&&

.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
ISSUED AT 720 AM EDT THU APR 30 2026

With any fog fleeting this morning, VFR conditions are now
expected through the period. Expect light and variable winds for
most of the time with winds at 10 kts or less.

&&

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

&&

$$

UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...MARCUS
AVIATION...GREIF