Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

311
FXUS63 KJKL 171113
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
713 AM EDT Sun May 17 2026

.KEY MESSAGES...

- Above normal temperatures are expected through Monday, and
  likely extending into Tuesday, with highs in the upper 80s to
  lower 90s.

- An extended period of unsettled weather is likely to develop
  toward midweek, with the potential for multiple rounds of
  showers and storms lasting into next weekend.

&&

.UPDATE...
Issued at 619 AM EDT SUN MAY 17 2026

The forecast is on track, with only minor updates needed to hourly
T/Td/Sky grids in the very near term.

&&

.SHORT TERM...(Today through Monday)
Issued at 257 AM EDT SUN MAY 17 2026

An upper-level high pressure system builds over southern Mid-
Atlantic region through the period, resulting in rising mid-level
heights across eastern Kentucky today through Monday. A shortwave
moving around the upper high tonight may bring some mid and upper
level clouds to the area, and increasing high clouds are possible
through the day Monday as the next system begins to move in our
general direction. Otherwise, the forecast is straightforward,
with strong subsidence and associated warming and drying resulting
in rapidly rising temperatures into the upper 80s to lower 90s
for daytime highs both today and Monday. Despite very warm
conditions, the combination of a drier air mass and good
radiational cooling conditions will result in continued ridge-
valley splits, with valley fog along the mainstem river valleys a
high likelihood late tonight into Monday morning.

.LONG TERM...(Monday night through Saturday)
Issued at 257 AM EDT SUN MAY 17 2026

An amplified ridging pattern yields much warmer than normal
temperatures across Eastern Kentucky for the start of the next work
week, but thankfully, that warmth will not persist for long. As the
week progresses, shortwave impulses will rotate around the base of a
broad, positively-tilted trough draped from the Southern Plains to
the Upper Midwest. The passage of those disturbances will culminate
in the suppression of the ridge, which places the Greater Ohio River
Valley in a regime of quasi-zonal flow for the second half of the
work week.

Low level flow becomes breezy and adopts a more southwesterly
orientation on Tuesday. This should correspond with increasing
moisture return and thus relatively greater sky cover on Tuesday
compared to Tuesday. As of now this doesn`t seem to impact the
temperatures too much, keeping similar highs to Monday - in the
upper 80s and low 90s. With more widespread dewpoints in the 60s,
diurnally-driven isolated to scattered showers and thunderstorms
enter the forecast. An approaching surface boundary lags off to the
NW of the CWA on Tuesday, meaning that any convection will lack the
frontal forcing and dynamic support aloft to be on the stronger
side. However, that forcing looks to arrive by Tuesday night and
Wednesday, producing more widespread shower and storms as the cold
front nears as passes through the CWA. The convective parameters and
location of storm development for Wednesday`s activity is
conditional on what happens upstream the previous day, so it is
difficult to pinpoint those specifics until we get closer to the
onset. However, the stalling nature of the boundary could cause
multiple rounds of convectively-bolstered rainfall to track across
the region through Friday. Most of this rain should prove highly
beneficial to the ongoing drought, and it will also work to lower
temperatures back towards seasonal averages through the end of the
period.

However, if it stalls out for too long over the forecast area amidst
the quasi-zonal flow aloft, the repetitive rainfall will get old.
There remains some model uncertainty on where this stall occurs
(along or south of the CWA) and how long it persists for. WPC has
outlined a broad-brushed Marginal Excessive Rainfall Outlook for the
region on Wednesday, but will be interested to see if this continues
into Thursday/Friday (New Day 5) to account for the continued
convection across the region. Widespread, significant flash flooding
is not the most likely forecast solution, but isolated instances
cannot be entirely ruled out if stronger storms track over the same
place multiple times in a row. Forecast confidence will increase
once this boundary`s approach enters the time range of the higher-
resolution, convective-allowing forecast model suite. For now,
confidence is highest in the thermal sensible weather effects from
this boundary. Expect highs to drop into the 70s to close out the
work week, with overnight lows returning to the 50s.

Unfortunately heading into the weekend doesn`t look to dry out any.
A shortwave will move into the Ohio Valley and amplifies lift and
instability once more, while keeping moist SW flow. This will
increase pops throughout the day once more, peaking with the
afternoon temperatures and diurnal mixing. The southerly flow will
help to boost temps slightly, with highs back into the upper 70s and
low 80s.

&&

.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
ISSUED AT 713 AM EDT SUN MAY 17 2026

VFR conditions are expected to prevail for the TAF period, with
the possible exception of fog formation late tonight in river
valleys, where localized VLIFR conditions will be possible through
12z Monday. However, this is not currently expected to affect any
of the TAF sites.

Southwest winds will increase to 5 to 10 kts areawide by midday
today, before decoupling around or shortly after sunset this
evening. Only occasional mid- and high-level clouds are expected
through the remainder of the TAF period, with a few to scattered
lower-level fair weather cumulus developing during peak heating
hours today.

&&

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

&&

$$

UPDATE...CMC
SHORT TERM...CMC
LONG TERM...MARCUS/JMW
AVIATION...CMC