Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

029
FXUS63 KJKL 232006
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
406 PM EDT Tue Jun 23 2026

.KEY MESSAGES...

- Showers will continue to gradually diminish through this morning
  over eastern and southeastern Kentucky.

- Lower humidity and dry weather arrive by late today and
  continue through Wednesday.

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

&&

.SHORT TERM...(This evening through Wednesday night)
Issued at 406 PM EDT Tue Jun 23 2026

The forecast guidance suite remains in generally good agreement with
the synoptic set up over the short term forecast period. Models
collectively resolve an upper level trough axis cutting directly
through our CWA this afternoon. That feature is progged to propagate
east into the Appalachians by sunset, which will place Eastern
Kentucky in a vertically stacked regime of northerly to
northwesterly flow. The resultant advection of a cooler and drier
continental airmass will persist aloft overnight, but surface winds
are forecast to calm overnight as a post-frontal high builds in. The
related subsidence favors efficient radiational cooling after dark,
and all signs point towards a rather foggy night in our CWA.

After widespread afternoon highs in the mid to upper 70s, expect
temperatures to quickly begin to cool towards lows in the 50s. A few
of the most sheltered and shaded valleys could see readings in the
upper 40s, but the aforementioned fog may wind up acting as
insulation. Thus, ridge-valley splits could under-perform the
magnitude suggested by some of the COOP MOS guidance. Given
antecedent dewpoints in the mid 50s, fog formation should first
occur in valleys with a water source. However, grounds across the
entire area were recently wet, and tonight`s fog will probably
develop outside of the river valleys too. Confidence in fog
formation is high across most of Eastern Kentucky, but there is less
confidence in the density of that fog. Area observations and webcams
will need to be monitored closely overnight, and future forecasters
may hoist SPS-type products for locally-dense fog tonight.

Whatever fog develops will likely lift towards the ridgetops and
then scatter out tomorrow morning, giving way to pleasant sensible
weather conditions. Aside from some passing high clouds and diurnal-
type cu, mostly sunny conditions are forecast. MaxTs will be a few
degrees below normal in the wake of today`s advection regime, with
highs in the upper 70s to near 80. Expect efficient diurnal
processes tomorrow night, with conventional summertime ridge-valley
MinT splits and overnight river valley fog included in the grids.

.LONG TERM...(Thursday through Tuesday)
Issued at 311 PM EDT TUE JUN 23 2026

There is reasonable agreement with the overall pattern across the
Ohio Valley for much of the long term. The period will begin with
upper high off toward the southeast near Bermuda. We will start to
see ridge riding shortwave troughs moving through the more locally
zonal flow aloft starting later Thursday. Most of the day looks dry
for most, with highs in the low to mid 80s. The first upper level
wave will pass across Kentucky Thursday night and this will lead to
increasing chances of showers and thunderstorms into the 20-60
percent range, with chances getting higher from south to north. This
as ample moisture starts to pump northward, with PWATs climbing
toward the 90th percentile for this time of year.

This more active pattern is then set to roll on with nearby surface
boundary becoming more stationary along the Ohio River and
additional waves passing through the Lower Ohio Valley. The next
shortwave is set to arrive by Friday and this is set to bring one
of the higher chances of rain, with values across the CWA
generally in the 60-90 percent chance range. The highest values
will be in the Bluegrass region and lessening as you move toward
the Tennessee and Virginia borders. The question as we move
through the period will be how much rain and where it will fall.
The ECMWF is showing some signals for heavier rain potential in
the EFI SOT, which could be a indicator for the potential for
flooding. However, there remains quite a bit of uncertainty still
with how much and where as mentioned before, but WPC does have
the area in a marginal excessive rainfall outlook for Friday into
Saturday morning for the threat. These series of shortwaves could
also be an indication of more of a MCS pattern and this will have
to be watched closely for stronger convection developing depending
on instability and timing of various rounds of convection.

Once we get toward early next week we will see upper level
ridging start to swing poleward from west to east. There is some
uncertainty with how far chances of rain will extend into the
week. There is at least some indication we will see better
moisture return start to reduce, as the flow become northerly
with time. Given the rising heights and dryer airmass a return of
much warmer weather is expected, with highs expected to climb
back into the lower 90s by Monday and Tuesday.

&&

.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 215 PM EDT TUE JUN 23 2026

The antecedent cloud deck continues to push southeast this
afternoon, with VFR conditions emerging at all TAF sites by the
18z issuance time. Breezy northerly winds and a shallow cu field
will subside after sunset, setting the stage for widespread fog
formation overnight. The greatest vsby reductions from this fog
will occur in valley locales and near area waterways. Thus, KSME
and KLOZ are progged to drop into MVFR flight rules after
midnight. These two terminals are the most likely to drop into IFR
before dawn, but KJKL and KSJS could experience similar
reductions as the fog lifts out of the valleys by daybreak.
Northern terminals will experience a deeper dry air advection
regime leading into the overnight period, and ensemble guidance
plots suggest that KIOB and KSYM are the least likely to reach
IFR. MVFR vsby drops were still included at these northern sites,
and observational trends will need to be monitored closely
tonight. Expect fog to lift and then scatter out tomorrow morning,
with both ceilings and visibilities well above VFR criteria by
mid morning.

&&

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

&&

$$

SHORT TERM...MARCUS
LONG TERM...DJ
AVIATION...MARCUS