Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

383
FXUS63 KJKL 092358
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
758 PM EDT Mon Mar 9 2026

.KEY MESSAGES...

- Unseasonably warm weather will last through Wednesday.

- A strong cold front will bring showers and thunderstorms
  Wednesday or Wednesday night, with strong winds possible.

- After a sharp cool-down Thursday, mild temperatures return for
  Friday into the weekend.

&&

.UPDATE...
Issued at 645 PM EDT MON MAR 9 2026

High clouds are moving in from the southwest early this evening.
Temperatures range in the lower to middle 70s but will fall back
into the 60s (50s valleys) as the sun sets. Clouds will continue
to increase and thicken as well through the remainder of the
evening.

&&

.SHORT TERM...(This evening through Tuesday night)
Issued at 346 PM EDT MON MAR 9 2026

Surface high pressure slipped to our southeast today and flow
around it is beginning to carry warmer air northeast into the
area. Our atmosphere is still dry for the time being, with plenty
of sunshine. Mainly clear skies lasting into the evening will
allow for radiative cooling, and combined with the warm air
advection will promote the development of ridge/valley temperature
differences. However, the low level flow is also carrying gulf
moisture northward and it will eventually advance northeast over
KY tonight to bring an increase in low clouds. That should impede
further drops in temperature overnight, with valleys possibly
creeping higher before dawn. Forecast soundings suggest the
increase in warm/moist air just off the surface will also lead to
instability developing over the region and allow for slightly
elevated, mainly scattered showers/thunderstorms to pop up
overnight. The precip potential will be enhanced by a weak mid-
upper level shortwave trough rippling through the zonal flow
aloft.

The shortwave trough will depart to the east early on Tuesday and
activity will probably decrease with the loss of upper support.
However, a few more showers/thunderstorms won`t be completely
ruled out after some warming and surface based destabilization
occurs during the day.

Forecast soundings show warming occurring near or just below 850mb
on Tuesday night without any further increase in moisture. As
surface temperatures cool, this would keep the lower levels
capped. However, increasing deep layer moisture in advance of a
large scale approaching upper trough will make the atmosphere
more conducive for precip. The greatest POP will be to our north,
closer to a strong surface low, but our POP will rise overnight
due to elevated moisture.

.LONG TERM...(Wednesday through Monday)
Issued at 522 PM EDT Mon Mar 9 2026

When the long term forecast period opens on Wednesday morning, the
area will be firmly positioned within the warm sector of a deepening
low pressure system centered over the Great Lakes. A strengthening,
vertically stacked regime of southwesterly low- to mid- level flow
will advect a warm/moist airmass into the region, leading to
multiple rounds of shower and thunderstorm chances. A round of this
activity will likely be ongoing as the sun rises, although it is
expected to be well below severe limits. Both the currently-
available deterministic model soundings and the HREF ensemble mean
soundings for 12z Wednesday depict an overnight radiation inversion
"capping" the atmosphere over our forecast area. However, hi-res
ensemble mean MUCAPE values over 750 J/kg and 30-40 knots of bulk
shear suggest that elevated thunderstorms will be possible during
the AM hours. The evolution of this morning activity will need to be
monitored closely as it push north-northeast towards the Ohio River.
Its leftover cloud coverage will play a large role in the forecast
for potentially stronger convection later on in the day/night, and
the rainfall it produces could result in locally wetter soils
ahead of any subsequent showers/storms.

As the sun comes up and diurnal warming/mixing takes place, the
aforementioned inversion is forecast to mix out. Models depict the
intensification of an 850mb LLJ over the Greater Ohio River Valley
headed into the afternoon hours, and momentum transfer soundings
suggest mixing heights up to this level. Combined, this favors gusty
southwesterly winds reaching the surface, and the forecast wind gust
grids were accordingly bumped up towards higher NBM percentile data.
Looking probabilistically at this non-thundestorm wind threat, the
12z LREF resolves a greater than 80% chance of maximum wind gusts in
excess of 30mph across the entire forecast area on Wednesday. If
this threshold is raised to wind advisory criteria (40mph), the
probabilities decrease to the 30-50% range and become limited to the
Bluegrass region and areas north of I-64. These northwestern
locations are closer to the core of that 50-60 knot 850mb jet
streak, which will also place them in a more favorable kinematic
environment for storms as the system`s cold front approaches on
Wednesday evening.

The thermodynamic environment for those storms remains more
uncertain. The strong southwesterly low level flow regime outlined
above will lead to efficient WAA and moisture return. Temperatures
should easily rise into the mid 70s within the warm sector on
Wednesday afternoon, but it is uncertain if the current forecast NBM
highs closer to 80 will come to fruition. Recent deterministic model
runs have been trending closer to that mid 70s range. This is likely
a byproduct of more persistent cloud coverage. Ensemble mean PWAT
values climb to between 1.25 and 1.40 inches as moisture continues
to stream into the column ahead of the cold front. The enhanced
moisture favors cloudier skies, which in turn, could also limit the
amount of surface-based instability realized on Wednesday afternoon.
Clearing currently appears most likely in southeastern KY, where
proximity towards SE CONUS ridging could foster deeper mixing. That
mixing would decrease surface dewpoints though, and thus, the
convective ingredients in the open warm sector look to juxtapose one
another. Discrete afternoon convection cannot be entirely ruled out,
but compounding forecast uncertainty precludes the mention of
specific details at this moment in time. As this event comes into
the temporal range of higher-resolution, trends in convective
parameter spacing will need to be monitored closely. For now though,
SPC has maintained a Slight (Level 2/5) Risk for Severe Storms
across the entire JKL CWA on Wednesday and Wednesday night.

The system`s cold front looks to pass through the forecast area on
Wednesday evening, and models resolve a steep temperature gradient
associated with FROPA. Thus, that boundary looks to provide ample
forcing for additional showers and storms to cross the area from NW
to SE after dark. Given the frontal forcing and strong deep-layer
shear, that activity could take the form of a squall line or a QLCS
upstream. This would favor damaging winds as the primary hazard type
with any evening storms, but this last round of convection will be
working against weaning instability as it enters our forecast area
around/after sunset. Furthermore, if afternoon/evening convection
comes to fruition, the atmosphere could be pretty worked over by the
time the front arrives. Thus, this could also turn into the classic
Eastern Kentucky severe weather situation where a QLCS decays as it
pushes further and further into our forecast area. System total
rainfall will need to be monitored if multiple rounds of activity
occur, but precipitation chances should quickly taper off once FROPA
occurs.

Winds shift towards the northwest behind the front on Wednesday
night, allowing colder air and a surface high to build into the
region to wrap up the work week. The chances for winter
precipitation on the system`s backside have dropped with this
forecast package, although a few flakes may still fly in the higher
terrain of SE KY early on Thursday morning. Expect drier, cooler
weather for the remainder of the work week as a result. CAA leads to
highs in the 40s and overnight lows in the 30 on Thursday. A
disturbance passes to the NE on Friday, but the dry air that moves
into the area behind the cold front will mitigate any substantial
precipitation chances with it. Temperatures moderate headed into the
weekend, with the next system progged to approach the area in the
late Sunday-Monday time frame. That system is forecast to usher in a
much colder airmass for the start of the next work week, and while
details are course at this temporal range, winter precipitation
cannot be ruled out on its backside.

&&

.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
ISSUED AT 758 PM EDT MON MAR 9 2026

VFR conditions were present at the start of the period and will
last well into the night as mid-high clouds increase and thicken
ahead of an approaching disturbance. Late tonight and Tuesday
morning, largely MVFR ceilings should develop over the region from
the southwest and west, along with scattered showers and
thunderstorms.

&&

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

&&

$$

UPDATE...GEERTSON
SHORT TERM...HAL
LONG TERM...MARCUS
AVIATION...GEERTSON/HAL