981
FXUS63 KJKL 132335 CCA
AFDJKL

AREA FORECAST DISCUSSION...CORRECTED
National Weather Service Jackson KY
635 PM EST Sat Dec 13 2025

.KEY MESSAGES...

- Another light, to possibly moderate, snowfall is on its way for
  this evening into early on Sunday, mainly north and east of a
  Stanton to Jackson to Whitesburg line.

- An arctic airmass moves into our region for late tonight through
  Sunday night with significantly below normal temperatures and
  bitterly cold wind chills in store.

- Near normal to above normal temperatures can then be expected
  from Tuesday through the end of next week.

&&

.UPDATE...
Issued at 633 PM EST SAT DEC 13 2025

Sent out a quick update for temperatures and to refresh wording to
remove "late afternoon" wording in the zone forecasts. The
forecast is overall on track.

&&

.SHORT TERM...(This evening through Sunday night)
Issued at 450 PM EST SAT DEC 13 2025

Late this afternoon, an upper level low was centered over the
northern Great Lakes/Ontario with an upper trough extending south
into the MS Valley and eastern Conus. A shortwave trough moving
through the upper level trough was nearing the Lower OH valley. At
the surface, a frontal zone continues to move further into VA and
TN. Cold high pressure was centered in the Dakotas and extended
through much of the central and northern Plains. The approach of
the shortwave trough as well as some jet dynamics/jet streak north
of the OH River is leading to widespread snow mainly near and
north of the OH River. A north to south temperature gradient is
also in place with low clouds having persisted in the north.

This evening and tonight, the upper level low is expected to track
to near the Lake Huron vicinity while the shortwave trough will
track through the OH Valley this evening and working east of
eastern KY late tonight. The 500 mb trough axis will begin to
approach late tonight. Ongoing cold advection will increase in
earnest this evening with 850 mb temperatures expected to fall to
near or below 0C during the evening and then to roughly the -10C
to -16C range around dawn on Sunday. Along with the passing
shortwave and some favorable jet dynamics/right entrance region in
the north this evening, the low level flow between the front to
the south and east and the cold high pressure over the Central
Conus will become increasingly upslope/northwest and low level
lapse rates will steepen. These factors should ultimately
determine QPF and ultimately amounts as moisture increases as the
shortwave nears and crosses the area. Low level moisture into and
above the DGZ should linger behind the shortwave. 850 mb
temperatures will cool to -16 to -20C late Sunday morning to early
Sunday afternoon as the mid level trough axis passes. Mid level
height rises follow. However, the lingering low level moisture,
upslope northwest flow, and continued cold advection should
support some isolated to scattered flurries at times during much
of the day on Sunday. The low level moisture will become
increasingly shallower Sunday evening and Sunday night and this
combined with warm advection should lead to some of the low clouds
decreasing though some could remain through the night as the sfc
high builds from the MS Valley into the Lower OH Valley and
settles across eastern KY. Lows could near the 0 degree mark
possibly to more of an areal extent than currently forecast
especially where there is any clearing and snowcover.

A period of snow is expected to gradually develop early this
evening in the north, with the precipitation more spotty and
likely mixed initially with rain in the southwest as the area of
precipitation gradually spreads south this evening into the
overnight hours. The snow should taper to snow showers from
northwest to southeast late tonight to early on Sunday. By late
evening into the overnight, the snow should also be more
convective in nature through the night and again, precipitation
should be more spotty in the southwest where the duration of omega
and deeper moisture will be shortest.

The convective allowing models, especially the HRRR have generally
been more pessimistic with snowfall for this evening into Sunday
morning though the most recent 20Z run is a bit higher than
several previous run. The recent RAP runs and NAMNEST have
generally a bit higher in the advisory area as are the global
models including the ECMWF AI. This leads to uncertainty in
snowfall totals. However, some snow expected to fall in the
advisory area combined with falling temperatures travel impacts
are anticipated even if totals end up only marginal for advisory
criteria on the southern and western edge of the advisory.

Wind chills late tonight into Sunday morning are forecast to near
and in some spots, mainly the westernmost tier of counties, reach
the lower end of the Cold Weather Advisory criteria. Wind chills
and or air temperatures should again near 0 degrees Sunday night.
For simplicity and better agreement with surrounding WFOs opted
to add Harlan County to the Cold Weather Advisory and also extend
the Advisory through Sunday night.

.LONG TERM...(Monday through Saturday)
Issued at 336 PM EST SAT DEC 13 2025

Monday morning, surface high pressure will be situated right over
Eastern Kentucky, which will bring mostly clear skies and light
southerly winds to the region. It will also feel like a frozen
tundra, as some of the coldest air of the season will remain
entrenched across the area from the previous arctic air mass that
moved through the Commonwealth over the weekend. Temperatures and
wind chills will be in the single digits early Monday morning. With
high pressure continuing to build across Kentucky, rising heights
will lead to temperatures warming into the low 30s around and north
of the Mountain Parkway, and mid to upper 30s along and south of the
Hal-Rodgers/KY-80 Highway.

Dry conditions should last through the better part of Wednesday, as
Eastern Kentucky remains in somewhat zonal flow through then. There
is some moisture that may creep into the Lower Mississippi Valley
Wednesday, morning, but at current POP chances for the southwestern
most counties remain just under 15%. North of the area, an upper
level low will be passing through the Upper Great Lakes, which pack
isobars through that area. Breezy conditions may translate as far
south as Eastern Kentucky. At current, gusts up to 20 mph look
possible, but conditions should otherwise remain fairly uneventful.

POP chances increase heading into Wednesday evening and Thursday, as
and another upper level trough begins to deepen over South-Central
Canada. Showers will develop out ahead of the systems warm front
early Thursday morning. While these showers are ongoing, a surface
cold front will be further west, somewhere through the Upper and Mid-
Mississippi valley. This trough looks to progress east and looks to
become somewhat negatively tilted by Thursday afternoon and evening.
There may be a chance for thunderstorms, however current chances
remain under 15%, so mention of thunderstorms have been left out of
the forecast at this time. Winds are expected to be out of the south
to southwest and could gust as high as 25-30 mph. By Thursday,
temperatures across the region could be in the upper 50s, and near
60 in some places. Once the cold front moves through the area Winds
become westerly and eventually light an variable later Friday.
Temperatures may be 10-15 degrees cooler than Thursday, with high
temperatures in the upper 30s to mid 40s. There are some signals of
another system approaching for next weekend, which would likely be
rain, but model spread is to great at this point to nail down any
specifics.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
ISSUED AT 627 PM EST SAT DEC 13 2025

Arctic cold front continues to move southeast across the
terminals, and as of 23z is on the cusp of reaching KJKL and KSJS,
and will shortly thereafter reach KSME and KLOZ by ~02z. Low
clouds to low-MVFR cigs or lower can be expected immediately after
frontal passage, with snow producing MVFR/IFR viz still north of
KSYM but expected to move southeast across the area between now
and 12z. KSYM and KSJS should see the longest duration of snow and
KSME and KLOZ the shortest duration. Skies will generally clear
gradually after 12z, likely first at KSME and KLOZ, but then
gradually reaching all terminals by the end of the TAF period,
with KJKL and KSJS seeing clouds and possible flurries lingering
the longest.

Generally, light and variable winds are expected initially before
winds become northwest at 5 to 10 KT by the 03Z to 06Z timeframe
as the arctic front passes, with potential gusts to near 20 KT in
the first several hours tonight after frontal passage.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 10 AM EST Sunday for KYZ044-
050>052-059-060-104.

Cold Weather Advisory from 1 AM Sunday to 10 AM EST Monday for
KYZ044-050>052-058>060-068-069-079-080-083>088-104-106-108-111.

Winter Weather Advisory until 1 PM EST Sunday for KYZ106>110-112-
113-115-118>120.


&&

$$

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