Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

697
FXUS63 KJKL 220108
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
908 PM EDT Thu May 21 2026

.KEY MESSAGES...

- Showers and thunderstorms return Friday. A few strong to
  severe storms are possible, bringing a threat for an isolated
  tornado or damaging wind gusts.

- An unsettled and wet pattern continues through the Memorial
  Day weekend and into next week with repeated rounds of rain
  and thunderstorms.

- Heavy downpours are likely with this activity. Total rainfall
  amounts of 1 to 2 inches are expected through Saturday morning
  with locally higher amounts and isolated flooding concerns.

- Despite the rain, it will be warm and humid through the holiday
  weekend with highs in the mid 70s to mid 80s.

&&

.UPDATE...
Issued at 720 PM EDT THU MAY 21 2026

Current radar imagery shows an area of showers ambling northeast
into our southern counties from Tennessee, where the frontal
boundary is currently located. This activity should decline over
the next few hours with the loss of daytime heating, but PoPs were
bumped up in this area over the next few hours to account for
this radar trend. Overnight, ample moisture and a temporary lull
in shower activity should allow for fog to set in for may
locations, so fog coverage was increased for tonight`s forecast.
Beyond that, temperature and dewpoint grids were freshened up to
reflect recent trends.

&&

.SHORT TERM...(This evening through Friday night)
Issued at 412 PM EDT THU MAY 21 2026

Low stratus and light rain, more showery in places, persist across
eastern Kentucky late this afternoon, and a frontal boundary remains
draped over far southern Kentucky from near Big Black Mountain
westward to the vicinity of Lake Cumberland. Thermometer readings
range from the mid to upper 50s north of the boundary to the mid 60s
further south. Looking aloft, subtle disturbances continue to ride
northeastward across the Lower to Mid-Ohio Valley along the
aforementioned boundary as upper level ridging lingers in the
vicinity of Bermuda and into the southeastern CONUS and troughing
extends from Central Canada southward into the Desert Southwest. A
shortwave trough passing through the base of the parent trough is
situated over East Texas and the Western Gulf.

A wet and showery pattern will continue through the short-term
period. The aforementioned frontal boundary will sag southward this
evening, leaving lingering damp conditions. The shortwave trough to
our southwest will then eject northeastward and lift across the Ohio
Valley on Friday and Friday evening. This will cause a wave of low
pressure to track northeast through the Mid-South and into the
western portions of Kentucky by Friday evening. A 30 to 40 knot 850
hPa jet in the low`s warm sector will send the frontal boundary
buckling back northward across as Commonwealth as a warm front
during the day on Friday while PWATs climb to 1.6 to 1.8 inches
in the LREF (or in excess of the 95th percentile relative to
climo). In addition to heightened moisture, this will also send
warmer and more unstable air back northward across the area,
leading to a renewed threat for thunderstorms across the forecast
area. While the CAPE profile will be skinny, MLCAPE will range
from 500 J/kg northeastern foothills to 1250 J/kg Lake Cumberland
area. Soundings also show considerable low-level shear (in the 15
to 20 kt range from the surface to 1 km) as well as fishhook
looping in the low-level hodograph, yielding 100 to 150 m2/s2 of
ESRH in tandem with ~30 kts of EBWD. As such, there is potential
for a few weak supercell structures, especially with potential
mesoscale dynamics near the warm front, perhaps generating an
isolated weak tornado or damaging wind gust. The greatest threat
of severe weather appears to be mainly west of I-75 and also
across locations north of the KY-80 and Hal Rogers Parkway
corridor from London eastward. Accordingly, much of eastern
Kentucky is under a Day 2 Marginal Risk (1 out of 5) for severe
weather on Friday. Additionally, given the high PWATs, skinny
CAPE, and potential for repeated rounds of convection, localized
hydro issues may become a concern with time. The 21/12z HREF LPMM
shows bullseyes of up to 4 inches by 12z Saturday morning.

In sensible weather terms, look for light rain and showers to
diminish from the northwest through the evening, leaving low clouds,
fog, and just some spotty showers. It will be mild tonight with lows
ranging from the mid 50s north to mid 60s south. Showers and
thunderstorms will become widespread again on Friday with warmer
temperatures ranging in the mid 70s north to upper 70s south.
Torrential downpours are likely, and an isolated brief damaging wind
gust or tornado cannot be ruled out with the strongest activity. For
Friday night, showers and thunderstorms, some with torrential
rainfall, will continue while temperatures settle back into the lower
and middle 60s for most locations.

.LONG TERM...(Saturday through Thursday)
Issued at 327 PM EDT THU MAY 21 2026

The forecast period begins with a surface low moving northeast
through the Mid-Mississippi Valley into the Ohio Valley. The
associated warm front is progged to lift slowly northward with the
surface low. This will usher in a WAA regime with climbing
temperatures; however, along with the rising temperatures,
widespread showers and thunderstorms will be likely. Highs Saturday
are forecast to be in the upper 70s to lower 80s, accompanied by a
nearly 100 percent chance of rain throughout the day. Forecast
soundings Saturday afternoon paint a picture of efficient rainfall
efficiency, while also hinting at a conditional strong to severe
storm threat. Precipitable water values are upwards of 1.60 to 1.70
inches. On the severe side, around 1500 to 2000 J/kg of SBCAPE will
exist alongside moderately steep lapse rates; however, vertical wind
shear is quite meager, which remains the primary limiting factor.
Even so, it would not be surprising if the SPC issues a Marginal
Risk. PoP values start to diminish for the overnight period as
diurnal instability wanes and the primary frontal forcing moves off
to the north. However, another surface low moving northeast will
quickly fill the void, allowing for increasing rain chances
beginning early Sunday morning.

Sunday brings another warm frontal passage with showers and
thunderstorms possible throughout the day. Temperatures start to
warm into the low to mid 80s behind the warm front, but the big
story will continue to be the ongoing shower and thunderstorm
threat. PWs climb higher Sunday into Monday as efficient moisture
advection shifts into the area behind the warm front. PW values will
climb to around 1.80 inches, exhibiting a skinny CAPE profile on
soundings with very little overall instability present hinting at
efficient rainfall taking place. This active pattern will continue
through the forecast period. Temperatures will remain largely
seasonal, but repeated rounds of showers and storms are expected.
Through the entire extended forecast period, the forecast total QPF
will range from over an inch in the Bluegrass/I-64 corridor, up to
2.00 inches in the Lake Cumberland area, and almost 2.50 inches
across the east-central part of the CWA. These numbers will
certainly fluctuate depending on convective activity and where
mesoscale bands set up, but nonetheless, this will be a wet Memorial
Day weekend into next week.

In summary, an active and unsettled weather pattern will dominate
the region through the holiday weekend and into next week as a
series of surface lows and warm fronts track across the Ohio Valley.
While robust warm air advection will pull seasonal temperatures into
the 70s and 80s, it will also transport deep, tropical-like moisture
into the area, yielding precipitable water values up to 1.80 inches.
This environment will support widespread, hydro-efficient rainfall
and embedded thunderstorms, with localized totals potentially
exceeding 2.50 inches across portions of the CWA.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
ISSUED AT 835 PM EDT THU MAY 21 2026

Showers and/or light rain persists in the wake of a frontal zone
stalled to the south of eastern KY. Low clouds and or stratus
build down fog was also common at issuance time with reductions
to IFR in many areas and in some cases to near or below airport
minimums. The boundary is expected to gradually lift north and
into eastern KY as a warm front as the period progresses. This
should lead to rounds of convection, but the low ceilings and IFR
and lower reductions should be commonplace for the first 12 hours
of the period north of the warm front. Then, gradual improvements
into the MVFR ranges are probable to end the period. Some
thunderstorms possible mainly during the last 6 to 9 hours of the
period. Winds will remain light through the period, generally
under 10 kts and primarily out of the northeast initially veering
to southeast to south with time.

&&

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

&&

$$

UPDATE...FAGAN/JP
SHORT TERM...GEERTSON
LONG TERM...VORST
AVIATION...FAGAN/JP