Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

280
FXUS63 KJKL 270100
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
900 PM EDT Sun Apr 26 2026

.KEY MESSAGES...

- A more active weather pattern will set up this week, with
  multiple chances for widespread showers and storms from Monday
  night through Wednesday.

- Severe weather potential remains masked by forecast uncertainty
  here in Eastern Kentucky, but a stronger line of storms is
  poised to approach the I-75 corridor early on Tuesday morning.

- Additional thunderstorms are possible later on Tuesday and again
  on Wednesday, and these will bring highly beneficial rainfall to
  the region.

- Once a frontal boundary finally clears the area late next week,
  cooler than normal temperatures are favored.

&&

.UPDATE...
Issued at 900 PM EDT SUN APR 26 2026

Forecast remains on track. Quiet conditions are expected this
evening with mostly clear skies. Diurnal temperature curves were
refreshed with the latest observational data from around the
area.

&&

.SHORT TERM...(This evening through Monday night)
Issued at 413 PM EDT SUN APR 26 2026

Seasonably mild temperatures are noted across eastern Kentucky this
afternoon -- thermometers range from the upper 60s in the northern
foothills to lower and middle 70s elsewhere under mostly sunny skies
and light, cool northeast winds. Surface ridging dominates over
the Ohio Valley from an extensive area of high pressure over the
Great Lakes and Eastern Canada. This is supported aloft by a 500
hPa ridge axis extending from the Mid-Mississippi Valley northeastward
to over Northern Quebec. An upstream trough is noted over Central
Canada and much of the Western CONUS and will be responsible for
our next notable weather.

The quiet weather will persist tonight and Monday as the ridging
shifts east of the Appalachians. This will yield mostly clear skies
tonight across the area (just a few passing high clouds) with
temperatures dipping back into the upper 40s to mid 50s for most
locations. A few of the typically colder northern hollows could
briefly dip into the mid 40s. Some patchy fog formation is
possible in the deeper sheltered Coalfield river valleys as well.
Southerly return flow will develop late in the night and continue
on Monday, ushering in noticeably milder air. Temperatures at 850
hPa rising into the 13 to 15C range should support afternoon highs
rising into the lower to mid 80s for most of the area under mostly
sunny skies.

By Monday evening, ridging will be departing as a leading shortwave
(within broader parent troughing) shifts across the Upper
Mississippi Valley and supports a deepening low pressure system
tracking from Wisconsin into north-central Ontario. Convection,
some of it strong to severe, is modeled in the CAMs to develop
over the Central Plains today within the system`s warm sector and
propagate eastward into the Mid-Mississippi and lower reaches of
the Ohio Valley on Monday. This convection, as well as additional
convection firing ahead of the system`s cold front, should
congeal into a QLCS structure and race eastward Monday night,
outrunning its parent forcing and eventually its instability
source as it moves from Central into Eastern Kentucky. As a
result, we can expect a weakening line of showers and
thunderstorms, likely with a period of trailing stratiform
precipitation, to quickly move across eastern Kentucky during the
early morning hours on Tuesday, likely bringing a widespread
0.25 to 0.50 inch rainfall. (Of note, a few isolated weaker
showers cannot be ruled out earlier Monday evening, especially
near and north of I-64 amidst increasing low-level warm air and
moisture advection.) SPC has maintained a Marginal Risk (1 out of
5) for severe weather across the northwestern two-thirds of the
CWA on Monday to account for the potential for isolated damaging
wind gusts with this QLCS. Also, temperatures on Monday night
will be milder than tonight, generally in the mid 50s, as mixing
should continue through the night amidst a 3-4+ mb surface
pressure gradient across the CWA.

.LONG TERM...(Tuesday through Sunday)
Issued at 708 PM EDT Sun Apr 26 2026

When the long term forecast period opens on Tuesday morning, the
main line of activity discussed above will likely be pushing out of
of our forecast area. Its parent cold front is poised to stall out
in the vicinity of the Ohio River as it gets abandoned by its upper
level support overnight, adopting more of a zonal orientation in the
process. This boundary could serve as the focal point for additional
showers and storms on Tuesday afternoon/evening, but there are
several limiting factors at play.

The boundary`s increasingly diffuse nature means that its forcing
will be rather weak at first. The wind grids are rather uniform, as
this afternoon`s forecast guidance suite collectively resolved
persistent and breezy southwesterly low level flow spreading across
the forecast area by midday. After a cool start to the day in the
upper 50s, the warm air advection associated with these winds will
allow temperatures to recover into at least the mid 70s by Tuesday
afternoon. It is uncertain how much warmer than that it will get,
and forecast highs have actually ticked a bit downwards relative to
this time yesterday. Some of this uncertainty is rooted in the
amount of cloud cover that lingers after the AM activity, especially
in southeastern portions of the forecast area. There, lighter rain
may linger behind the line for a few hours, meaning that they will.
experience less solar insolation than areas that clear out quicker.
As such, relatively cooler temperatures are forecast closer to the
VA state line, but this may yield a differential heating
boundary. If that boundary begins to shift north during the
afternoon WAA, a locally enhanced area of convergence could
emerge, but otherwise, it will take reaching convective
temperature thresholds (generally in the upper 70s) to trigger CI
on the warm side of the boundary. The currently available
deterministic BUFKIT soundings are mixed on whether or not this
threshold is met at sites in northern and western sites around the
CWA, but any cells that do develop could take advantage of the
modeled 40 knots of 0-6km shear to become organized into
supercell-esque structures. This activity would be inclined to
propagate east-southeast into the cooler air across SE KY, and
interactions with any mesoscale boundaries will need to be watched
closely. Modeled hodographs show some modest low-level curvature,
but they are generally linear. This suggests that hail and
damaging winds would be the primary hazards with any discrete
convection, unless a right- mover is able to facilitate a
mesoscale accident. Convective trends will need to be monitored
closely on Tuesday afternoon as higher resolution guidance
becomes available, but the discrete thunderstorm risk currently appears
conditional.

There will be another chance for strong to severe thunderstorms on
Tuesday evening as a shortwave ejects out of the Ozarks and into
the Lower Ohio/Tennesseee River Valleys. Ahead of this feature,
moisture will be pooling on the south side of the stalled
boundary. This results in a crescent-shaped corridor of dewpoints
above 60 degrees stretching from the Lake Cumberland region
through the I-75 corridor and into the Bluegrass region along
I-64. In the mean LREF data, this corresponds with a narrow tongue
of 1000-1500 J/kg of MUCAPE by 8PM Tuesday evening. The dynamic
lift provided by the approaching negatively-tilted trough should
combine with strong midlevel flow to provide enough lift and bulk
shear for organized storm clusters. These clusters will want to
ride the instability gradient into our CWA from the west. The
greatest CAPE values are generally resolved in southwestern
portions of our CWA, near Lake Cumberland, and SPC has placed
Wayne, Pulaski, McCreary, and Whitley counties in a Slight (Level
2/5) Risk for severe storms on Tuesday. The rest of the forecast
area is denoted in a Marginal (Level 1/5) Risk, largely due to the
conditional nature of the afternoon risk and the potential for
multiple failure modes. One of the factors that could result in a
forecast bust is convective cloud debris blowing off stronger
convection to our southwest in the Tennessee Valley. Machine
learning guidance is more aggressive with the severe probabilities
to our southwest, and the activity there could rob us of the
necessary instability for stronger storms. The core of the
nocturnal low-level jet with this system is also relegated to the
Tennessee Valley. This reduces the amount of low-level shear
available to storms, so damaging wind gusts and hail would be the
primary hazard types with any sustained storm clusters on Tuesday
evening. It is also plausible that that upstream activity once
again weakens as it moves into our CWA, and Tuesday`s
afternoon/evening convection will remain a low-confidence forecast
until the exact evolution of the morning activity becomes clear.

Any convection that occurs on Tuesday will cause the stalled
boundary to creep towards the south, as will the ejection of Tuesday
night`s shortwave. The surface low associated with this disturbance
will move through the Ohio River Valley on Wednesday morning and
pull the boundary southeast into the CWA. Depending on what time
FROPA occurs, one last round of thunderstorms is possible in our CWA
on Wednesday afternoon. That forecast is shrouded by the compounding
uncertainty from Monday and Tuesday, but the further south and east
one goes into the CWA, the more likely this third round of activity
becomes. The approaching front, the digging of a more robust trough
aloft, and the area`s positioning in the vicinity of the left exit
region of a 300mb jet streak should provide enough lift for
precipitation. Likewise, the strength of the midlevel flow should
maintain the approximately 40 knots of effective bulk shear. The
thermodynamic environment is highly uncertain though. While
Tuesday night`s cloud cover will insulate lows to readings around
60 degrees, there is less of a signal for skies to clear after
sunrise on Wednesday morning. Forecast highs are notably cooler
(upper 60s to lower 70s) on Wednesday than the previous two days,
which keeps the mean LREF instability values in the 500-1000
range. A HSLC (high shear, low cape) type set-up cannot be ruled
out with any frontally forced convection, but the available
ML/AI/Analog guidance only resolves low-end, marginal-type severe
probabilities across the southeastern third of the forecast area
on Wednesday. At the very least, this third round of activity will
cement the notion that some highly beneficial rainfall is in
store for Eastern Kentucky this week.

As convective-allowing models enter the ensemble blend used t
populate the storm total QPF grids from Monday evening through
Wednesday night, forecast rainfall totals have become more spatially
variable. Localized, streaky maximums have emerged in locales
where models track multiple rounds of convection, but the highest
totals are generally confined to the Cumberland River Basin. The
LREF ensemble probabilities for at least than 1 inch of
precipitation from all of this activity have trended downwards
with the last two model cycles, but greater than 50% probabilities
remain in the vicinity of Lake Cumberland and in the Bluegrass
region. These are the same areas with the highest dewpoints
leading into Tuesday evening`s rainfall, and climatologically
speaking, they experience more efficient moisture return. In the
Big Sandy Basin and along the Virginia state line, the
probabilities have decreased to between 40 and 50%. This is likely
due to the effects of downsloped southeasterly flow ahead of
Monday night`s precipitation, which yields locally drier air in
the lower levels and undercuts accumulation via evaporative
processes. The final round of precipitation may make up for this,
but when all is said and done, the area`s QPE minima is likely to
come in the eastern portions of the CWA. However, a wetting rain
(> 0.25 inches of precipitation) is almost certain, with > 95%
probabilities resolved area-wide for this threshold. All rain that
falls will prove highly beneficial to the ongoing drought across
Kentucky, and it should quench some of the earlier spring fire
weather concerns. The antecedent dryness does mean that the ground
should be able to soak up most of the precipitation that falls,
but given the potential for multiple rounds of convection, WPC has
maintained a Marginal (Level 1/4) Excessive Rainfall Outlook for
the southern half of the CWA on Tuesday. Widespread fluvial
flooding remains unlikely, but nuisance ponding of water cannot be
ruled out in urban corridors and the typical poor drainage areas.

Deeper mid to upper level troughing digs into the Ohio River Valley
headed into the weekend. Strengthening WNW flow aloft will work to
advect a cool, continental airmass into the forecast area, and the
aforementioned, stubborn frontal boundary is poised to finally shift
out of the CWA on Thursday. Precipitation chances and sky cover
tapers off as drier air filters in throughout the column, giving way
to highs in the 60s and lows in the 40s. These readings are below
climatological norms for Eastern Kentucky at the end of April, and
reinforcing shots of colder air arrive in the region as shortwave
disturbances rotate around the base of the broader troughing to kick
off the month of May. The odds for precipitation with these
disturbances appear to be decreasing, and there has been a trend
towards a cutoff upper level low developing in the NE CONUS next
weekend. Such a pattern favors below normal temperatures in
Eastern Kentucky for the first days of May. The CPC extended-range
hazard outlook is centered around these colder temperatures due
to their potential to cause a frost, and their 6-10 day
temperature outlook now highlights a 60-70% chance of below normal
temperatures across the greater Ohio River Valley. Those with
interests sensitive to frost (such as agricultural crop producers
or recreational gardeners) are accordingly encouraged to continue
to monitor for updates as the calendar turns to May. As of the
time of writing, the coldest nights look to be in the May 2nd to
May 4th time frame.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
ISSUED AT 703 PM EDT SUN APR 26 2026

VFR conditions should prevail through the TAF period. Expect
mainly high clouds at times. Fog is possible tonight in the most
sheltered river valleys but is not expected to impact the TAF
sites. Winds will generally be light and variable at less than 10
kts through tonight before becoming southerly at 5 to 10 kts after
14Z on Monday.

&&

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

&&

$$

UPDATE...GINNICK
SHORT TERM...GEERTSON
LONG TERM...MARCUS
AVIATION...GEERTSON/GINNICK