952
FXUS63 KJKL 111437 CCA
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
845 AM EST Thu Dec 11 2025

.KEY MESSAGES...

- A clipper system is on track to produce a widespread and
  impactful accumulating snow tonight into Friday morning. A
  Winter Weather Advisory is in effect for this system over much
  of eastern Kentucky.

- Another light to moderate snowfall is increasingly likely
  Saturday night and early Sunday.

- An arctic airmass with well below normal temperatures moves
  into our region for Sunday.

&&

.UPDATE...
Issued at 845 AM EST THU DEC 11 2025

Winter Weather Advisories were cancelled as the substantive snow
showers have departed. Forecast remains largely on track. Expect
more clouds than sun today with high temperatures mainly in the
low to mid 30s.

&&

.SHORT TERM...(This afternoon through Friday evening)
Issued at 620 AM EST THU DEC 11 2025

Snow showers are diminishing from the northwest this morning as
any Great Lakes moisture fetch is cut off, the low levels dry
out, and cold air advection wanes behind last evening`s cold
front. Any additional roadway impacts from the departing activity
will likely be confined largely to elevations above 1,500 feet.
Temperatures are in the lower 30s across most of the area, except
generally in the 20s above 1,500 feet. The latest weather maps
show the cold front sliding off the Atlantic Seaboard while deep
500 hPa troughing is in place over the eastern CONUS around an
~502 dam parent low over the Ottawa Valley. A ridge of high
pressure runs along the Mississippi River. Well upstream, a low is
developing in the lee of the Rockies over Montana and Alberta,
under robust vort max energy.

That energy, along with its weak surface reflection, will dive
southeast into the aforementioned 500 hPa trough today, crossing
eastern Kentucky late tonight and Friday. A vast majority of the
system`s precipitation will be induced by isentropic upglide on
the front end of the system. Model guidance consistently shows a
WAA precipitation band developing out ahead of the low center and
propagating southeast from the Dakotas, Upper Midwest, and
Lower/Central Ohio Valley, leaving an ~150 to 200 mile wide
northwest to southeast-oriented swath of light to moderate snow
accumulation. Model guidance has been consistent in showing light
to moderate snow amounts over the Big Sandy Basin and north of
the Mountain Parkway near the center of the band, with more
uncertainty further south and west due to potential shifts in the
band`s track and limited access aloft to the DGZ leading to low
SLRs or even some light mixed precipitation. As the low moves
through, precipitation appears to largely come to an end on Friday
morning, and the system`s cold front will bring little in the way of
fanfare and only a subtle push of colder air late in the day. The
Winter Weather Advisory for this system was extended further south
to capture those counties favored to average at least 1 inch of snow
accumulation, roughly coincident with the 11/00z HREF PMM snowfall.

In sensible terms, look for leftover snow showers to taper to
flurries between ~7 to 8 AM over southeast Kentucky. Clouds
remain prevalent for much of the day, and it stays cool with highs
only in the lower to middle 30s. Snow quickly develops from west
to east after sunset this evening (~7 to 10 PM), while
temperatures settle back into the upper 20s to lower 30s. The snow
will gradually taper from southwest to northeast later in the
night and on Friday morning (maybe ending as a brief mix). Snow is
likely to persist longest in the northeast, likely leaving the
highest amounts (2-4 inches) north of the Mountain Parkway and
over the Big Sandy River Basin, dwindling to little in the
vicinity of Lake Cumberland. Even once precipitation tapers on
Friday, clouds remain persistent. It will overall be milder,
though, with high temperatures ranging from the mid 30s in the
north to near 50 along the TN/KY border.

.LONG TERM...(Friday night through Wednesday)
Issued at 416 AM EST THU DEC 11 2025

The extended forecast window opens with lingering, post-frontal
upslope snow showers stemming from Fridays preceding clipper system.
Weak surface high pressure is forecast to build into the area, but
this will be very short-lived as extended model guidance and
associated ensembles remain in strong agreement and maintain
consistency regarding a subsequent fast-moving clipper system. This
second system is projected to track across the central CONUS,
reaching the CWA vicinity by late Saturday night into Sunday.

Very few significant changes have occurred with respect to the
temporal and spatial components of this incoming feature. The PoP is
expected to increase Saturday afternoon. This system is generally
forecast to maintain a more northerly track. With this northerly
trajectory, the heaviest precipitation is concentrated north of the
CWA, primarily along and north of the Ohio River. However, of note,
some model trends suggest a potential southward shift in the track,
and a few guidance runs have hinted at this possibility. This
potential shift would have significant consequences on anticipated
snowfall totals, the placement of the freezing line, and which areas
receive frozen versus liquid precipitation. Nonetheless, the highest
snow accumulations are currently forecast along and north of a line
from Powell to Pike Counties through Sunday morning, but this
delineation could change should the feature shift north or south.

Unseasonably cold surface high pressure will subsequently build into
the region behind the departing low-pressure system on Sunday,
advecting some of the coldest air of the season thus far through the
early part of the succeeding week. A gradual warming trend is
expected by the middle of next week, preceding the approach of
another synoptic system for Wednesday.

In summary, the period will be characterized by the passage of two
distinct clipper systems. Lingering post-frontal snow showers will
initiate the period from the first clipper, and a second fast-moving
clipper is forecast for Saturday night into Sunday. There remains
some uncertainty regarding total snowfall accumulations with the
Saturday/Sunday system, but at a minimum, the issuance of Winter
Weather Advisories will be necessary to cover this expected event.
Strong surface high pressure will subsequently establish itself over
the region on Sunday, driving minimum temperatures down to the upper
single digits and mid-teens. A notable warm advection regime ahead
of the next system is forecast to commence by Wednesday.

&&

.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
ISSUED AT 747 AM EST THU DEC 11 2025

MVFR ceilings, with a few breaks possible at times, will persist
through the day. Another fast-moving clipper low will bring a
period of steady snow tonight leading to deteriorating conditions
this evening and early overnight. The worst conditions (IFR or
worse) are anticipated over the northeastern half of the CWA,
including JKL, SJS, and SYM. The precipitation will be lightest
and of shortest duration near Lake Cumberland and heaviest and
persistent north of the Mountain Parkway. Winds will be westerly
at less than 10 kts today becoming light variable to southerly
tonight.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 7 PM this evening to 10 AM EST
Friday for KYZ044-050>052-058>060-068-069-088-104-106>115-
118>120.


&&

$$

UPDATE...GEERTSON
SHORT TERM...GEERTSON
LONG TERM...VORST
AVIATION...GEERTSON