Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

843
FXUS63 KJKL 190430
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1130 PM EST Sun Jan 18 2026

.KEY MESSAGES...

- A dry cold front passing eastern KY late tonight and Monday
  morning will usher in a colder and drier airmass, with single
  digit lows expected for most places Monday night.

- Temperatures averaging 10 to 20 degrees below normal will be in
  place over the area through Tuesday night.

- The next chance for snow will come Wednesday night, although
  accumulation potential appears limited.

&&

.UPDATE...
Issued at 1127 PM EST SUN JAN 18 2026

Main edits were, once again, to Sky grids with the late evening
update, with the forecast being rather quiet through the overnight
period.

UPDATE Issued at 942 PM EST SUN JAN 18 2026

Mid-level cloud deck has moved over the area a littler earlier
than expected, so made edits to the Sky grids to account for this.
Otherwise, the forecast is on track.

UPDATE Issued at 619 PM EST SUN JAN 18 2026

The forecast remains on track. Mid-level cloud cover moving into
the region may be a bit fast compared to what is in the grids,
with minor tweaks to Sky grids to try and account for this.

&&

.SHORT TERM...(This evening through Monday night)
Issued at 350 PM EST SUN JAN 18 2026

As of mid afternoon, an upper level low was centered in the vicinity
of northern Hudson Bay, with a trough extending south into the
Upper MS Valley and Great Lakes south to the Gulf Coast. Further
west, an upper level ridge extended from Mexico across southwest
sections of the Conus to west of the west coast of Canada. A
shortwave trough that crossed the area this morning to midday was
shifting east of eastern KY with a weak shortwave upstream nearing
the Lower OH Valley. Further upstream, additional shortwaves were
rotating through the trough and around the upper low in the Hudson
Bay area. The first extended into the upper to middle MS Valley
and was approaching the western Great Lakes. While a second was
rotating across the northern Ontario to Manitoba vicinity and yet
another was further north in Canada. At the surface, a ridge of
high pressure was centered in the South TX to northern Mexico area
with this sfc ridging extending into the TN and OH Valleys. A sfc
low associated with the shortwave trough that is nearing the
western Great Lakes region was located in the western Great Lakes,
with a cold front trailing to SD to MT. Cold sfc high pressure was
in place north of this boundary, centered in Canada.

This evening and tonight, a weak shortwave is progged to move across
the Lower OH Valley region, while the next stronger upstream
shortwave moves across the western and Central Great Lakes and OH
Valley. The next shortwave upstream of that nears the western
Great Lakes tonight. Meanwhile, the surface low preceding all of
this should trek to the Lake Huron/Ontario vicinity through
tonight, with the trailing cold front sweeping across the Western
and Central Great Lakes to the Lower OH Valley to the Southern
Plains. A period of mid level clouds is anticipated per
deterministic guidance as well as the 12Z HREF from this evening
into the early part of the overnight as the shortwave passes the
Lower OH Valley region. A few flurries could fall from the passing
mid level clouds in the north during the late evening to around
the midnight hour, and chances for flurries were included for a
couple hours in the Fleming County vicinity, but due to dry lower
levels this may end up as just virga. Some at least initial
valley decoupling and ridge/valley splits are probable this
evening and perhaps extending into the overnight. As the front
nears, however, the pressure gradient will increase as will winds
aloft. Winds should pick up on the ridges and in the more open
terrain areas during the second half of the night, with some
gusts to around 20 mph possible late. Winds and gusts late tonight
were hedged toward the higher percentiles of the NBM particularly
for western locations. Any areas that manage to decouple in
between rounds of thicker clouds should become mixy by late in the
night. Lows are expected to range in the upper teens to low 20s.

Monday to Monday night, the upper level trough is expected to remain
in place from Canada into the Central and Eastern Conus, downstream
of ridging over sections of the eastern Pacific into the western
Conus. Additional shortwaves are progged to move across the Great
Lakes region, generally passing north of the Commonwealth/OH
Valley. The sfc low in Canada should tack across parts of Ontario
and Quebec and approach the Maritimes Monday to Monday night. The
trailing cold front should cross eastern KY Monday morning, with
sfc high pressure building across the Plains and Central Conus
beginning to build into the Lower OH Valley as the day progresses
and ushering in a colder and drier airmass. This ridge of high
pressure should become centered in the TN Valley vicinity as the
period ends.

As the front passes Monday morning and also behind it, the pressure
gradient will remain rather robust well into Monday afternoon and
mixing of higher momentum from aloft should result in gusts
between 20 and 30 mph, with a few stronger peak gusts possible.
Sustained winds and gusts were hedged toward the higher percentiles
of the NBM on Monday to better account for the frontal passage
with BUFKIT momentum transfer also supporting the higher gusts.
Near and behind the boundary late tonight and especially Monday
morning, model guidance such as the 12Z operational GFS and the
12Z HREF means suggest there should be a period of saturation or
near saturation in a layer around 850 mb down to near 925 mb and
clouds in this layer would intersect the DGZ. This and westerly
flow in the low levels may be sufficient for a few flurries to
reach the surface particularly the northern portions of the area.
For now, flurries have not been included in the forecast for
Monday though the potential will continue to be monitored.

Confidence remains high regarding continued below normal temperatures.
Highs Monday should reach the mid 20s north to low 30s in portions
of the south and the southeastern valleys. With high pressure in
place and dry dewpoints, many locations should fall into the
single digits to around the 10 degree mark for lows with min
Apparent temperatures in the single digits for most. Winds will
be generally light with high pressure in place, but may stay
strong enough in the more open terrain locations in the northwest
and across the high terrain above 2500 feet for Apparent Temps to
possibly bottom out in the single digits below zero. These values
would be nearing cold weather advisory criteria at least briefly.

.LONG TERM...(Tuesday through Sunday)
Issued at 254 PM EST SUN JAN 18 2026

The forecast period begins with cold surface high pressure
reinforced by northwesterly flow aloft. While the period starts dry,
CAA will favor well-below-average temperatures Tuesday. Forecast
highs are expected to range from the mid-20s in the Bluegrass to mid-
30s in the south. During the day, upper-level flow will shift from
northwesterly to westerly, becoming southwesterly by Wednesday
morning. This will begin to advect warmer air into the region
Tuesday night; however, mostly clear skies will allow for strong
radiational cooling, keeping lows in the low teens within sheltered
valleys and near 20 on ridgetops. Temperatures are expected to rise
late Tuesday night as southwesterly flow strengthens. This shift is
courtesy of a shortwave diving out of the Canadian Rockies. By
Wednesday morning, the associated trough and surface low will move
into the Great Lakes. Pre-frontal WAA will lead to highs reaching
the low to upper 40s. A cold front is progged to move through the
Commonwealth; thermal profiles appear supportive of an initial rain-
snow mix transitioning to all rain. As temperatures fall behind the
front, a transition back to a rain-snow mix is expected Wednesday
night into early Thursday morning. Little to no accumulation is
expected, and any snowfall will be slushy and confined mainly to
elevated surfaces. Confidence regarding moisture availability and
total snowfall remains low, as deterministic models and their
ensembles lack agreement. The GFS is trending colder, suggesting
more snowfall, while the ECMWF remains warmer and drier. The current
forecast represents a blend of these solutions, favoring a wintry
mix over a pure rain or snow event.

Thursday brings the return of weak surface high pressure that will
prevail through much of the period. Upper-level zonal flow will
allow daytime temperatures to range from the lower 30s to lower 40s
on Thursday, warming into the upper 30s to upper 40s by Friday.
Another pattern shift is forecast for the end of the period, with
the potential for wintry precipitation next weekend. Confidence is
low as models show significant run-to-run inconsistency, but a trend
is developing toward a more active pattern by the end of the week.

In summary, the period begins with well-below-average temperatures
under cold surface high pressure. An approaching cold front
associated with a clipper moving through the Great Lakes is expected
mid-week. Rain and a rain-snow mix with minimal accumulation are
expected through early Thursday before high pressure returns for the
remainder of the work week.

&&

.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
ISSUED AT 1129 PM EST SUN JAN 18 2026

VFR conditions are generally expected to prevail through the
period, with the conditional threat for a few hours of borderline
MVFR cigs diminishing across the far north between around 12z and
16z Monday.

Light southwest winds generally around 3 to 7 kts initially this
evening will increase to near 10KT between 06Z and 12Z especially
for western terminals as a cold front approaches, with gusts into
the 20 to 25KT range during the day Monday along and behind the
cold front before beginning to diminish toward the end of the TAF
period.

&&

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

&&

$$

UPDATE...CMC
SHORT TERM...JP
LONG TERM...VORST
AVIATION...CMC