Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

460
FXUS63 KJKL 241811
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
211 PM EDT Wed Jun 24 2026

.KEY MESSAGES...

- Lower humidity and dry weather continues today.

- Unsettled weather returns to end the week and into the weekend,
  with rounds of showers and storms possibly producing heavy rain
  and a flood threat.

&&

.UPDATE...
Issued at 943 AM EDT Wed Jun 24 2026

The previous forecast remains largely on track, with lingering
valley fog burning off under mostly sunny skies this morning.
Temperatures are quickly recovering into the upper 60s, and
western locales should approach 70 by the top of the next hour. As
such, have bumped MaxT grids up by a degree or two later this
afternoon. Expect efficient diurnal warming/mixing processes to
persist through this evening as a surface high pressure system
sits directly overhead.

UPDATE Issued at 628 AM EDT WED JUN 24 2026

Increasing high clouds and even a deck of stratocumulus have
helped keep fog a bit at bay, with many webcams showing low
stratus instead of fog. Made some tweaks to Sky grids for the next
few hours to account for these trends, and updated hourly T/Td
grids likewise.

&&

.SHORT TERM...(Today through Thursday)
Issued at 255 AM EDT WED JUN 24 2026

A broad longwave trough remains entrenched across the northern US,
with an unusually active jet stream continuing from the Northern and
Central Plains east through the Mid-Atlantic and Northeast. At the
surface, high pressure is centered over eastern Kentucky and will
slowly give way to increasing southwesterly low-level flow Thursday
ahead of the next system approaching the area to end the week.

A trio of weak and progressive disturbances cross the area today and
tonight but will only generate some thin mid- and high-level clouds.
With a good amount of filtered sunshine highs will begin to rebound
from yesterday`s cool temperatures, reaching the upper 70s to lower
80s, still a few degrees below normal. Lows tonight will continue
their upwards trend, with mid 50s in the valleys to lower 60s on the
ridges, with widespread river valley fog expected once again.

Warm advection increases through the day Thursday as a jet streak
moves east to the northern Ohio Valley region, with dewpoints
rising into the mid to upper 60s by late afternoon, especially
west of the escarpment. Showers and thunderstorms will develop
along and ahead of a front situated from the center of the country
east through central IL/IN/OH by 00z Friday, with low-end PoPs
starting to be introduced late in the period to the north of the
Mountain Parkway corridor. High temperatures Thursday will return
to near normal readings for late June, generally in the mid to
upper 80s.

.LONG TERM...(Thursday night through Tuesday)
Issued at 255 AM EDT WED JUN 24 2026

The long term period will open with an upper level high located off
of the southeast Atlantic coast, with additional upper level ridging
over Texas, northern Mexico, and southern AZ/NM. To the north, an
upper level low will be located between the Great Lakes and the
Hudson Bay, with general upper level troughing over the Great Lakes
region. Locally, eastern Kentucky will remain in quasi zonal flow
aloft as the area is sandwiched between these features, leaving the
forecast area in an active pattern going into the weekend. At the
surface, an area of low pressure will be located near Lake Huron,
with a cold front draped over southern Ohio and Indiana. Meanwhile,
a series of 500 mb shortwaves will translate eastward into the Ohio
Valley region early Friday morning. Associated height falls
overspreading eastern Kentucky should provide additional lift for
showers and storms, meaning Friday and Saturday are expected to be
rainy, with showers and thunderstorms likely throughout the day.

Activity on Friday and Saturday will bring a risk for heavy rainfall
and perhaps isolated to scattered flash flooding. There are some
indications that these shortwaves could lead to the formation of a
secondary surface low over the Ohio Valley, which could eventually
enhance southwesterly flow over the forecast area, leading to
further moistening of the environment. Regardless, PW values are
expected to be high on Friday and especially overnight Friday into
Saturday, when 12Z LREF mean PW values are in the range of 1.7-1.9
inches (generally in the 90th percentile or higher for the
forecast area). An analysis of ensemble members reveals high
confidence in this moist environment, with relatively small spread
in PW beyond a slight skew in the distribution towards higher PW
values in some members. As a result, instances of flash flooding
cannot be ruled out with this activity, and WPC has highlighted
the area with Slight Risk (Level 2/4) Excessive Rainfall Outlooks
for Days 4 and 5 (Friday and Saturday) to account for this
possibility.

A few questions remain regarding this flood risk. First, the exact
positioning of the aforementioned front will affect the most favored
corridor for higher QPF, especially given strong moisture
convergence, the expectation that the front will become quasi-
stationary, and general boundary-parallel southwesterly flow that
could allow for training storms (with particular concern for our
area on Friday). The general model trend right now is to keep the
boundary north of the Ohio River before it lifts further north,
relegating the highest QPF to the northern extremities of our
forecast area, but this trend will bear monitoring with subsequent
forecasts. Additionally, with a series of impulses aloft, complexes
of storms capable of producing flash flooding may also be possible.
Some machine learning guidance has highlighted a low-end risk for
damaging winds with thunderstorm activity on Friday and Saturday;
however, this remains contingent on the development of adequate
instability (something which may be difficult to realize if showers
and storms are ongoing), and shear looks to be quite marginal
(generally 20-30 kts), so there is low confidence in any severe risk
at this time.

By Sunday, upper level ridging will build over the Mississippi
Valley, leaving eastern Kentucky in northwest flow aloft. This will
allow for one more day of potentially disturbed weather before upper
level ridging amplifies further and overspreads the forecast area.
With height rises over eastern Kentucky, weather will be hot and
rain chances will be low, with highs in the 90s returning by early
next week. Without a mechanism to sweep out the moisture associated
with previous activity, dewpoints should also remain high (likely in
the 70s), so this will not be a dry heat; weather will be muggy into
the end of the period.

&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
ISSUED AT 214 PM EDT WED JUN 24 2026

VFR conditions are forecast to prevail at the TAF sites for the
duration of the 18z issuance period. A field of cumulus clouds
has developed this afternoon across the region. These should
subside after sunset, perhaps giving way to some passing high
level clouds overnight. Conditions are primed for river valley fog
formation after 04z, but this is still not expected to affect any
of the TAF sites. Observations will need to be monitored in the
Cumberland region (KLOZ and KSME) as this time frame approaches,
as there is a low-end chance (less than 25 percent) for fog-
related MVFR vsby reductions in the LAMP guidance for these
terminals. In general, expect light and variable winds and non-
impactful sky cover to persist into tomorrow morning. Winds adopt
a more southwesterly orientation and strengthen to speeds greater
than 6 knots towards the very end of the TAF period tomorrow
afternoon, when another cu-type cloud field is expected to
develop.

&&

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

&&

$$

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