Somerset, Kentucky 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

745
FXUS63 KJKL 212041
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
441 PM EDT Tue Jul 21 2026

.KEY MESSAGES...

- A strong cold front could produce multiple rounds of
  thunderstorms this afternoon and into the first part of the
  overnight.

- There is a Slight to Enhanced Risk for severe storms this
  afternoon and evening, including damaging winds, large hail,
  and isolated tornadoes.

- Torrential rainfall from persistent thunderstorms could lead to
  flash flooding during this time.

- Mainly dry weather is expected from Wednesday night to Friday,
  with temperatures averaging about 5 degrees below normal.

&&

.SHORT TERM...(This evening through Wednesday night)
Issued at 316 PM EDT TUE JUL 21 2026

The incoming cold front is the big story this afternoon and evening,
as storms have developed ahead of the boundary and are dropping
south and southeast. An upper level shortwave is also going over the
Great Lakes region, creating deep troughing across the Ohio Valley
this afternoon With a primed environment, especially in our northern
CWA where sheer and CAPE are at their highest, all severe modes are
on the table. A Severe Thunderstorm Watch has been issued through 2Z
for the NW 2/3 of the CWA, and a Flood Watch for flash flooding is
in effect for all of eastern KY through 6Z. The biggest concern
remains straight line wind gusts and torrential rainfall with any of
the storms that move through , however, hail and isolated tornadoes
are still on the table. Best instability and shear will slowly
decrease as the storms continue farther southeast this evening and
we start to lose daytime heating/instability, but the storms are
still forecast to make it to the TN and VA border by around midnight.

Heading into the overnight, showers and storms will continue along
the TN border as the cold front slows it`s progression through
eastern KY and deep troughing remains in place across the region.
For locations north of the remaining storms and boundary, drier
air will begin to filter in as winds slowly turn more northward.
However, expect clouds to likely stick around through much of the
night. Kept fog in the forecast, but again did not confine it to
just the river valleys given that most of the CWA will have residual
moisture in place with cooling temperatures.

Tomorrow - Wednesday - will be very opposite of today, thankfully.
Some lingering showers/thunderstorms may be possible along the TN/VA
border as the boundary remains a bit more stationary to our south,
but the remainder of the CWA will continue to see high pressure
build in from the NW. Humidity will be reduced, with temperatures
topping in the upper 70s to low 80s. Models try to show clouds
mixing out throughout the afternoon, but overall there may still be
some cloud cover in place through much of the day.

The filtering of cold air into the region will really be evident
going into Wednesday night. Especially if clouds are able to
continue to clear out, temperatures will drop into the upper 50s to
low 60s, some 10 degrees colder than tonight`s temperature forecast.
Any clearing could also promote fog development, especially in the
deeper valleys that are both cooler and more moisture ridden. Kept
with the previous forecast of valley fog during the overnight.

.LONG TERM...(Thursday through Tuesday)
Issued at 440 PM EDT TUE JUL 21 2026

At the onset of the long term period, upper level troughing will
sit over the northeast CONUS, with an additional area of troughing
associated with a closed upper level low located off the Pacific
Northwest coast. Ridging will prevail between these features and
will be centered over the Southern Plains at the start of the
extended period, with anomalously high 500 mb heights across much
of the central and western CONUS. Locally, eastern Kentucky will
find itself in a region of northwesterly flow aloft for several
days, with the forecast area sandwiched between ridging and
troughing. At the surface, an area of high pressure near the Great
Lakes will keep winds northeasterly on Thursday, ushering in
cooler and drier air. Highs will struggle to rise above the low
80s, and with dewpoints falling into the upper 50s and low 60s,
Thursdays weather will be downright pleasant. Overnight, lows will
plummet into the upper 50s and low 60s, with typical fog
formation in our mainstem river valleys.

PoPs will return by Friday afternoon as a shortwave embedded
within northwesterly flow aloft rotates into our area. Ahead of
this shortwave, the eastward translation of the aforementioned
surface high will allow winds to gradually become more northerly
to northwesterly over the course of the day. This will allow for
modest moisture advection, and given shortwave forcing, isolated
to scattered storms will be possible near the VA line on Friday
afternoon. With the potential for additional embedded impulses,
rain chances will continue through Saturday, although the timing
and details of this activity will need to be refined in later
forecast periods. By Sunday, the northeast trough will deepen
along the Atlantic Coast, with flow aloft becoming increasingly
northerly over the forecast area. Model spread increases
significantly at this point, with rain chances dependent on
embedded impulses that are difficult to resolve this far out. For
now, slight to chance PoPs are forecast through the end of the
period, although uncertainty remains high at this time.

&&

.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 324 PM EDT TUE JUL 21 2026

A bit of a volatile TAF situation this afternoon. While most TAFs
are currently VFR, a line of showers and thunderstorms is
currently located to our NW and will push SE throughout the rest
of the afternoon and evening, affecting the TAF sites as it does.
Expect VIS and CIGS to quickly be reduced in any storms that move
through the TAF sites, with heavy rain, frequent lightning, and
damaging wind gusts being the primary threats. Tried to time out
the line in each of the TAF sites, but expect it should move
through and exit within 3 and 4 hours from arrival. Outside of
any storms, conditions should be VFR, though can`t rule out some
fog development, especially behind the exiting storms overnight.
Predominate SW to Wrly winds are breezy this afternoon, but will
diminish into the overnight outside of any storms as well, staying
generally light and variable into the day Wednesday. While some
lingering low clouds may stick around overnight tonight, expect
things to begin mixing out during the daytime hours Wednesday as a
strong area of high pressure continues to build in.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
Flood Watch until 2 AM EDT Wednesday for KYZ044-050>052-058>060-
068-069-079-080-083>088-104-106>120.

&&

$$

SHORT TERM...JMW
LONG TERM...FAGAN
AVIATION...JMW