Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

733
FXUS63 KJKL 260153 AAA
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
953 PM EDT Sat Apr 25 2026

.KEY MESSAGES...

- A more active weather pattern sets up early next 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 925 PM EDT SAT APR 25 2026

Showers have moved into VA at this time, though some convective
allowing models suggest the potential for a couple of additional
showers or sprinkles over the next couple of hours in the southeast.
Nighttime microphysics and area ASOS/AWOS obs indicate a mixture
of clouds near 5kft agl, low stratus, and probably some fog as
well. This leads to uncertainty as to the development of fog
versus low stratus overnight or even the potential for a
continuation of fog where clouds have thinned in the east and
southeast following rainfall. Northeastern/eastern locations may
eventually end up with some of the stratocu and stratus currently
in WV and southeast OH moving into the area or developing further
southwest per guidance as well. For now, have made no changes to
areal extent of the stratus, but will be following trends for
valley fog in the south and may make some adjustments accordingly.

&&

.SHORT TERM...(This evening through Sunday night)
Issued at 405 PM EDT SAT APR 25 2026

Showers and even a few rumbles of thunder are noted over eastern
Kentucky late this afternoon as a cold front departs into Virginia.
Weak instability and weak shear are limiting updraft strength and
organization. Cloud cover has been most persistent in the
southeastern third of the forecast area, keeping temperatures
there mainly in the 60s. Further northwest where some sunshine has
managed to break through in the drying post-frontal air mass,
thermometers have recovered into the lower to middle 70s. Aloft, a
vort max is noted upstream from Huntington to Elizabethtown
embedded within a subtle 500 hPa shortwave trough. Meanwhile at
the surface, a subtle trough extends from the Central Appalachians
to over southwestern and western Ohio. Further north, surface
high pressure dominates over much of eastern Canada.

Most of the lingering showers and any thunderstorm activity will
gradually depart with the decaying cold front this evening with most
to all activity exiting into Virginia by around 6 PM. Behind that,
most areas should be dry overnight; however, the weak surface
trough will drop south from Ohio with time while the vort max
crosses the area ever so slowly during the evening and first half
of tonight. Thus, a rogue isolated shower cannot be ruled out deep
into the night, primarily over the Big Sandy basin and adjacent
counties. Behind that trough, weak north to northeasterly flow (10
to 20 kts at 925 hPa) will usher low-level moisture southwestward
across the area overnight. While radiation fog may form initially
in valleys where clearing occurs this evening, there is a
heightened potential for a low stratus deck to develop
southwestward as this low-level moisture and modest flow interact
with the slight upward topographic incline south of the Ohio
River. Locations over the Cumberland River Basin have the lowest
confidence in being impacted from any low stratus as the moisture
is modeled to arrive there latest in the night or early Sunday
morning. Should this stratus deck materialize, any fog that
develops in affected valleys earlier in the night should tend to
fade while the stratus ceilings could drop low enough to shroud
the ridges. Look for lows ranging from the mid 40s to low 50s.

Weak high pressure ridging then builds in on Sunday from the high
over eastern Canada and yields slow continued drying on a light
northeasterly breeze. Morning low clouds and lingering fog should
gradually lift and break revealing mostly sunny skies by afternoon.
It will be seasonable and dry with highs in the lower 70s northeast
to upper 70s southwest. Dry conditions and fair skies persist Sunday
night under high pressure with overnight low temperatures forecast to
range from the mid 40s in colder northern valleys to mid 50s near
Lake Cumberland and on thermal belt ridges.

.LONG TERM...(Monday through Saturday)
Issued at 638 PM EDT Sat Apr 25 2026

The forecast period opens on the back side of this weekend`s
shortwave ridging, with breezy southerly winds advecting warm air
into Eastern Kentucky. Afternoon highs are forecast to climb towards
the mid to upper 80s under mostly sunny skies. Efficient diurnal
mixing should yield wind gusts up to 20mph and 30-40 degree dewpoint
depressions. A few warm-sector pop up showers cannot be ruled out in
western portions of the area on Monday afternoon, but their
intensity ceiling will be limited by a lack of deep moisture and the
displacement of the forcing/lift out to the west in the Mississippi
River Valley. Forecast guidance has trended more northwesterly and
later with the parent low associated with Monday`s well-advertised
severe weather risk. Stronger thunderstorms are still expected to
initiate in Western Kentucky on Monday evening, and it may organize
into a QLCS as it pushes east across the commonwealth overnight.

Ahead of that line, flow in the lower half of the atmospheric column
turns veers towards the southwest and intensifies. Models resolve
the intensification of the 850mb low level jet to between 50 and 60
knots after dark, which results in more effective moisture return
into our forecast area. This correlates with a nocturnal surface
warm frontal passage and the potential for weaker WAA-type showers
out ahead of that main line. PoPs accordingly increase from SW to NE
after sunset, and mean LREF PWATs climb to upwards of 1.25 inches by
the time the line arrives on Tuesday morning. However, the line will
be working against the diurnal instability curve, and the potential
for nocturnal radiation inversions could suppress the eastern extent
of its severe weather risk. Breezy wind profiles will yield ample
shear, especially the further northwest one goes. A mean 40-45 knots
of bulk shear is resolved across the northwestern 2/3 of the CWA by
8am Tuesday, and the spatial footprint of this local shear maxima
overlaps with the SPC Day 3 Marginal Severe Weather Outlook. While
that outlook is technically labeled as Monday`s risk, it is
actually for the early Tuesday AM activity in the JKL CWA. This
outlook primarily exists for locally damaging thunderstorm wind gust
potential, but the most likely solution is that a weakening line of
storms becomes elevated in nature as it approaches the I-75
corridor. The greatest overlap between favorable ingredients for
severe weather is not currently over our part of Kentucky for this
first wave of active weather, but regardless, we will be closely
monitoring the evolution of the upstream convection on Monday
evening.

Said evolution will prove highly consequential to Tuesday`s sensible
weather forecast, as it could leave residual outflow boundaries that
act as focal points for additional convection later that
afternoon/evening. The forecast guidance suite continues to keep the
actual surface cold front to the northwest of the area on Tuesday
afternoon, and that day`s temperature forecast has accordingly
increased. The previous night`s warm air advection and cloud
coverage will keep AM lows well above normal readings closer to 60,
and breezy prefrontal southwesterly winds will remain in place
across most of the forecast area into the evening hours. This allows
afternoon highs to climb towards the upper 70s/lower 80s again,
especially in SE KY. Tuesday afternoon`s airmass will be much more
moist than Monday`s though, with forecast dewpoints now in the upper
50s/low to mid 60s. A shortwave disturbance looks to propagate
towards the Ohio River Valley aloft during this time frame, meaning
that any additional storms could overlap with the diurnal
heating/instability cycle. LREF mean soundings across southern
Kentucky on Tuesday evening resolve approximately 1000 J/kg of CAPE
and 40 knots of effective bulk shear. The related hodographs are
curved in the lower levels, suggesting that a HSLC (high shear, low
CAPE) type set-up may come to fruition with this second wave of
activity. During the last long term SPC forecast package, there was
too much compounding forecast uncertainty leftover from Monday
night`s risk for a Day 4 Severe Weather Outlook this far north.
However, ML/AI/Analog guidance continues to tick Tuesday`s PM severe
weather potential upwards, and interests should continue to monitor
for forecast updates. Confidence is increasing that an active
baroclinic zone will set up through midweek, and if convective
activity isn`t realized on Tuesday, then Wednesday may come into
play.

As guidance has trended slower with Monday`s first wave of
convection and stronger with Tuesday`s second, it has collectively
kept the parent boundary in the vicinity of the forecast area on
Wednesday. With quasi zonal flow aloft, the forcing for any
additional midweek storms lies in mesoscale details that are hard to
pinpoint at the extended temporal range. However, the 12z LREF
ensemble data suggests that there may be conditionally favorable
parameter spacing for another round of stronger thunderstorms on
Wednesday. The likely stationary nature of the frontal boundary and
long/straight ensemble mean hodographs mean that this risk is likely
marginal, but the 12z deterministic models placed Eastern Kentucky
in the vicinity of the left exit region of a zonal 300mb jet streak
around the base of a digging upper level trough. If the resultant
synoptic lift overlaps with the warm side of that boundary and
mesoscale convective enhancements within our CWA, some stronger
(potentially splitting) cells cannot be ruled out. At the very least
though, this set up will lead to some highly beneficial rainfall.

Storm total QPF from Monday evening through Wednesday night
generally sits between 1.25 inches in the Northeast/Big Sandy Basin
to 1.75 inches in the vicinity of Lake Cumberland. The model blend
used to populate these grids currently sits outside of the temporal
range of the higher-resolution CAMS, so expect more spatial
variability and the potential for locally-enhanced totals in the
final storm total QPEs. The LREF Ensemble probabilities generally
follow the same lower to higher NE to SW gradient when it comes to
receiving at least 1 inch of measurable rainfall over that 60 hour
time frame. The highest exceedance probabilities (around 75%) are
currently in the Cumberland River Basin, with values closer to 55%
in our northeastern counties. Given that the KJKL and KLOZ climate
record sites are both currently below their climatological rainfall
averages for the month of April and the year to date, this rain is
welcome to fall. Given the potential for convectively-enhanced
higher amounts and the signal for multiple rounds of convection,
WPC has placed southern counties in a Marginal (Level 1/4) Excessive
Rainfall Outlook. The dry ground should be able to soak most of this
rainfall up, and widespread river flooding is unlikely in the
various hydro ensembles, but nuisance-type ponding of water is
possible in the typical areas of poor drainage. Ideally, all of this
activity is able to put a dent in the widespread D1 (moderate) to D2
(severe) drought currently observed across Kentucky.

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; they give
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. While these disturbances may
yield additional precipitation chances, increasing model spread
makes it difficult to pinpoint timing and magnitude details.
Guidance previously depicted a southern stream system brushing the
CWA next weekend, but the 12z suite backed off this idea. The time-
lagged NBM ensemble smooths out the PoPs related to that system and
the troughing perturbations into low end chances to close out the
forecast period, but the more impactful sensible weather is likely
to be observed on the thermometers at the start of may. The
overarching synoptic pattern favors below normal temperatures for
the first days of May, potentially reaching much below normal
readings on May 2nd and 3rd. The CPC extended-range hazard outlook
is centered on these colder temperatures due to their potential to
cause a frost, and their 8-14 day temperature outlook highlights a
50-60% 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
encouraged to monitor for updates as the calendar turns to May.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
ISSUED AT 835 PM EDT SAT APR 25 2026

A couple of stray showers or sprinkles are possible south of the
TAF sites over the first couple hours of the period. Otherwise,
fog is expected to form in valleys and areas with the more
substantial rainfall across the south where breaks in the clouds
occur, but TAF sites are still not expected to be affected by the
fog at this point. What fog would likely lift any areas where a
low cloud deck currently over southeast OH and WV drifts in from
the northeast or developing southwest into the area overnight. The
fog/and or stratus deck could bring a period of MVFR or worse
conditions to affected locales through as late as 13Z to 14Z, and
this may affect locations as far west as KSYM to KJKL. A longer
period of potential stratus was included in the TAF for KSJS.
Otherwise, fog, low clouds, and/or status should mix out between
13Z and 16Z. Generally, winds should be light and variable or
north to east at less than 10K through the period.

&&

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

&&

$$

UPDATE...JP
SHORT TERM...GEERTSON
LONG TERM...MARCUS
AVIATION...JP