Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

004
FXUS63 KJKL 081250
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
850 AM EDT Fri May 8 2026

.KEY MESSAGES...

- Frost is expected form in a few of the normally colder valley
  locations around dawn.

- A warming trend begins today with afternoon highs returning to
  the mid 70s to low 80s by Sunday.

- Periodic chances for showers and thunderstorms return to the
  area this weekend, with the greatest chances on Sunday night.

&&

.UPDATE...
Issued at 850 AM EDT FRI MAY 8 2026

Refreshed the diurnal temperatures with the latest observational
data from around the area, and updated the forecast with the
cancellation of the Frost Advisory this morning. No major changes
to the forecast, as everything remains on track.

UPDATE Issued at 750 AM EDT FRI MAY 8 2026

Minor adjustments were made to hourly grids based on trends in
valley fog that is generally located south of the Mtn Pkwy and for
hourly temperatures. Temperatures bottomed out in the 32 to 36
degree range in the deeper valleys and have begun to recover. The
frost advisory will likely be cancelled early within the next
hour as temperatures gradually rise out of the mid 30s in the cold
spots.

&&

.SHORT TERM...(Today through Saturday)
Issued at 515 AM EDT FRI MAY 8 2026

Early this morning, south of an upper low in the Hudson Bay area, a
broad trough was in place from portions of the central to eastern
Conus as well as central to eastern Canada. Upper ridging was in
place across parts of the Caribbean and the Gulf while another
ridge extended from the eastern Pacific into the western Conus. This
pattern leaves the OH Valley and eastern KY in west northwest
flow aloft. Several shortwave troughs were upstream, including one
that extended from the upper MS Valley to parts of the Central
Plains with a couple of additional shortwaves moving around the
ridge and into the trough tracking across Alberta and Manitoba.
At the sfc, a ridge of high pressure extended from the
Appalachians to the TN Valley and across eastern KY. This has
resulted in clear or mostly clear skies with some high clouds
passing across the south. Valley fog has developed in the deeper
valleys and along the rivers and lakes to the south of the Mtn
Pkwy. Mid 30s were observed in the deeper valleys and low lying
rural areas while coalfield ridgetop locations were in the low to
mid 40s. A home weather station, PWS in Morgan County recently
recorded 33 degrees and some frost may form or may have already
formed in the coldest southern and eastern valleys.

Today and tonight, initial valley fog and any frost should
dissipate within 2 to 3 hours past sunrise. Otherwise, the broad
upper level troughing is progged to remain across parts of the
central and eastern Conus. The first in a series of shortwaves
moves from the upper MS to central Plains regions to the Great
Lakes to Lower OH Valley region by this evening and tonight. Sfc
high pressure shifts east and southeast of the area today, while
guidance has 500 mb height rises through the morning. However,
some height falls occur by evening and into tonight as the
shortwave tracks across the Lower OH Valley. This shortwave moves
east of eastern KY on Saturday, followed by height rises in the
afternoon. The shortwave to cross the area later tonight into
Saturday morning will have limited moisture to work with. However,
sprinkles if not isolated to scattered showers are anticipated,
especially in the north.

Temperatures moderate to nearer to, but still below normal today
reaching the upper 60s in the north and low to mid 70s south.
Clouds are likely to be slow to thicken and lower with mid level
clouds likely not arriving until after midnight in the south.
This should result in the southern and eastern valleys decoupling
and a moderate ridge/valley temperature split. The airmass warms
further on Saturday under southwest to west flow and high
temperatures are forecast to reach near normal.

.LONG TERM...(Saturday night through Thursday)
Issued at 612 AM EDT FRI MAY 8 2026

The long term period opens with broad upper level troughing over
the northeastern US and mostly zonal flow over Kentucky. At the
surface, weak high pressure will build Saturday evening. Clear
skies will allow for radiational cooling overnight, although
westerly to southwesterly flow will maintain dewpoints in the
upper 40s to low 50s before winds diminish overnight. These clear
skies and light winds will set the stage for a ridge-valley
temperature split, but respectable dew points will likely prevent
valleys from cooling further than the upper 40s; although MOS
guidance is attempting to hint at lows in the mid 40s for some
valley locations, even 10th percentile LREF guidance keeps
dewpoints too high for this scenario to be realized. As a
consequence of this moisture, patchy fog development will be
favored in river valleys as temperatures approach dewpoints in
our valleys, although this fog should dissipate quickly as
temperatures begin to climb on Sunday morning.

Sunday will be the warmest day of the long term period. High
temperatures will rise into the upper 70s and low 80s, although
this warmer period will be relatively short lived. A cold front
extending from a low pressure system on the ON/QC border will
push into Kentucky throughout the day, with the highest rain
chances for eastern Kentucky overnight. Given warm temperatures
ahead of the front, instability will be low, but nonzero. Thus,
thunderstorms will be possible, although given meager CAPE and
unfavorable diurnal timing these storms are not expected to become
severe. The most likely outcome will be additional much-needed
rainfall. 00Z LREF guidance shows high confidence in PWATs greater
than 1 inch (90% chance ahead of the front), with median LREF QPF
sitting at around 0.25 inches for most of the forecast area; this
is higher than the NBMs current output, and this is without
accounting for potential convective effects. Therefore, increases
in QPF may be needed in future updates if the current moist trend
holds.

Following the frontal passage, northerly to north-northwesterly
winds will advect colder air into the area, leading to the
coolest highs of the period on Monday, even as skies clear
throughout the day. Aloft, the axis of the aforementioned trough
will pass over Kentucky, ushering in a pattern of persistent
northwest flow at the upper levels as high pressure begins to
build at the surface. This high will keep skies clear overnight
Monday night, allowing for another ridge-valley temperature
split. With dewpoints currently forecast to be in the mid 30s,
valley fog would be the main concern with this cooling; however,
given such a thin margin between fog and frost, trends will need
to be monitored. Should dewpoints run slightly lower (which is not
out of the question per ensemble guidance), frost potential would
increase.

By Tuesday, the surface high will shift out of our area ahead
of our next system. Flow will become more southerly, initiating
WAA and allowing high temperatures to climb into the upper 60s to
low 70s. This wind shift will also begin a period of modest
moisture return. Aloft, a prominent shortwave will provide upper
level support for a surface cyclone centered somewhere around the
Great Lakes region. Present guidance shows significant variance in
the timing and progression of this shortwave. The NBM is
outputting PoPs in the 30-60% range late Tuesday into Wednesday,
although this is primarily a function of temporal discrepancies
among different solutions rather than a true chance of rain.
Regardless of these discrepancies, it appears this system will
bring another opportunity for measurable precipitation by midweek.

&&

.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
ISSUED AT 753 AM EDT FRI MAY 8 2026

High pressure shifting across the area has led to clear skies and
light winds and resulted in IFR or lower fog some of the deeper
river valleys. Other than KSME, the TAF sites have not been
affected. Other than this fog lingering as late as 13Z to 14Z,
VFR is anticipated through the period. An increase in mid and high
clouds will occur after 18Z as a disturbance and weakening front
approach. A few showers or sprinkles are not out of the question
after about 03Z through as late as 15Z, especially for KIOB and
KSYM, but probabilities are less than 30 percent and even within
these, sub VFR conditions may not occur. Winds will be light and
variable to begin the period, becoming south to southwest at less
than 10KT after 14Z. Winds will slacken again to end the period.

&&

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

&&

$$

UPDATE...GINNICK
SHORT TERM...JP
LONG TERM...FAGAN
AVIATION...JP