189
FXUS63 KJKL 101103
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
603 AM EST Wed Dec 10 2025

.KEY MESSAGES...

- Southwesterly wind gusts to between 30 and 35 mph are likely
  today, with locally higher gusts possible. Lake Wind Advisories
  are in effect for the Cave Run Lake and Lake Cumberland areas.

- Snow showers are expected to produce spatially variable
  accumulations and localized travel impacts on tonight into
  Thursday morning. The greatest snowfall accumulation and impact
  will be above 1,500 feet ASL where a Winter Weather Advisory is
  currently in effect.

- A clipper system is expected to produce more widespread winter
  precipitation on Thursday night into Friday morning.

- A much colder than normal airmass is forecast to move into the
  region for this upcoming weekend.

&&

.SHORT TERM...(Today through Thursday)
Issued at 603 AM EST WED DEC 10 2025

Temperatures are a solid 15 to 25 degrees warmer across eastern
Kentucky this morning compared to just 24 hours ago, ranging
mainly in the 40s at all but the higher elevations. Southwesterly
winds across the area continue to strengthen as the pressure
gradient tightens between an ~990 mb clipper low over Lake
Michigan and an ~1018 mb surface high over the Southeast CONUS.
Gusts in the 20 to 30 mph range are noted in the more exposed
terrain, and generally 10 to 20 mph in more sheltered valley
locales. Looking upstream, composite radar reflectivity shows an
area of precipitation across much of southern Indiana and Southern
Illinois ahead of the clipper`s well-defined cold front, which
stretches from the surface low near Chicago southwest through St.
Louis and to over the western Ouachita Mtns. Within the broader
cyclonic flow aloft, a pronounced high-amplitude shortwave trough
is noted at 500 hPa over the Upper Midwest.

That shortwave trough will dive southeast today, carving out a
deeper 500 hPa trough over the Eastern CONUS. It reaches maximum
depth over our region around 6Z tonight with the passage of a
secondary shortwave/vort max, before gradually pulling east with a
couple of trailing vorticity lobes transiting the area: the first
between midnight and 7 AM Thursday, and the second during the day
on Thursday. Meanwhile, the surface low will continue to deepen
to near 980 mb as it speeds from the Southern Great Lakes to the
Canadian Maritimes by Thursday evening. As the warm conveyor belt
jet crosses our area our area this morning, look for an uptick in
winds; perhaps even the strongest winds of the day for some
locations will occur before the aforementioned area of stratiform
precipitation arrives and partially stabilizes the low-levels for
a time. A second maximum in strong wind gusts is expected as
lapse rates steepen again immediately along a behind the
aforementioned cold front. Modeled mixed layer momentum transfer
values strongly support gusts in the 30 to 35 mph range, especially
during the noted favored timeframe, and could exceed 40 mph at a
few spots.

The cold front mentioned previously should reach the western
border of the CWA by around 3-4 PM and exit the east by 6-7 PM.
Model guidance consistently shows that band of light stratiform
rain out just ahead of the front, forced by a potent leading vort
lobe. That will be followed by convective banded precipitation
along the cold front itself. RAP13 model soundings show steep
lapse rates up to 700 mb with the frontal passage, likely
supporting a mix of rain and graupel with convection along the
boundary, perhaps mixing with all snow within or on the backside
of the heaviest convection. There appears to be a second boundary
associated with a 700 hPa vort lobe that drops in from the north,
reaching Fleming County around 7 PM and exiting through southeast
Kentucky by around 9 to 10 PM EST. The air mass behind the second
boundary will be cold enough for an area-wide transition over to
snow. A period of strong 20 to 40 kt northwest upslope flow with a
moist > 80% RH 925 to 850 hPa layer will favor orographic snow
shower enhancement, especially over the higher mountains near the
Virginia-Kentucky border through the remainder of the night. This
potential has warranted the issuance of a segmented Winter
Weather Advisory from Pike down to Bell Counties. Most locations
above 1,500 feet should pick up 1 to 2 inches, and some of the
2,000 foot+ elevations on and adjacent to Big Black Mountain could
pick up 2 to 4 inches. Additionally, much of the guidance suggests
that the low-level flow will be northerly enough for a fetch
directly off of Lake Michigan. While the winds will back more
westerly with time, one or more pronounced lake-enhanced bands or
even an outright snow squall could reach down into our forecast
area, with best chances northeast of US-421. This has warranted
added mention of a snow shower threat tonight in the ongoing SPS.
The overall anticipated transient nature of the squalls prevents
inclusion of any additional counties in the Winter Weather
Advisory at this time. However, if certainty for a more sustained
and focused band of lake-enhanced snow increases, additional
counties may be considered. Snow showers should gradually wind
down to just some flurries from west to east on Thursday with
overall relatively little additional accumulation. Surface high
pressure briefly tries to nose in from the west later in the day.

In sensible terms, look for a windy day with two peaks: during
the morning/midday hours and again during the late afternoon and
evening. Gusts of 30 to 35 mph from the southwest to west should
be commonplace. Additionally, look for rain to reach Fleming
County 7 to 8 AM and drop southeast to near the Virginia border
by 2 PM EST. Precip will overall be light and may last less than 1
hour west of I-75, versus a couple of hours further north and
east. After the steady rain ends (possibly mixed with snow in the
highest elevations), additional showery activity follows, and
precipitation types transition over to all snow at lower
elevations by around 8 to 10 PM. Some of the snow showers could
be briefly heavy. Winds will gradually diminish overnight, with a
similar though slower decline in snow shower activity lingering
into Thursday. Temperature-wise, look for highs in the mid 40s to
low 50s (north to south) today, lows in the mid 20s tonight, and
highs in the lower to middle 30s on Thursday.

.LONG TERM...(Thursday night through Tuesday)
Issued at 326 AM EST WED DEC 10 2025

The forecast period commences with the approach of an Alberta
Clipper, tracking southeast toward the Commonwealth. At the onset of
the forecast, this surface low is anticipated to be traversing the
Central Plains. Analysis of forecast wind patterns and isotherms
suggests that the warm front will remain south of the area, and as
this system tracks from the Central Plains into the Ohio Valley, the
forecast area will be situated within the precipitation shield north
of the warm frontal boundary. Deterministic models and their
ensemble members exhibit strong consensus regarding this systems
trajectory across Missouri into Kentucky before its eventual
northeastward ejection toward the Mid-Atlantic states. Given this
path, the forecast area is expected to be bisected by the crucial
540 dam critical thickness line. Although the precise location of
this boundary is subject to spatial and temporal shifts with
subsequent model cycles, the overall trend indicates a north-to-
south split in p-types across the CWA. The northern half of the CWA
will likely experience accumulating snow, while a wintry mix is
anticipated along the freezing line, transitioning to all rain
further to the south. Providing exact accumulation values for the
northern CWA is premature; however, the current forecast supports
the potential need for Winter Weather Advisories from Thursday night
through Friday morning to address the snow hazard.

Following the departure of the first system, a weak surface high
pressure is forecast to build back into the area. Model guidance
maintains consistency regarding a subsequent Clipper system tracking
through the central CONUS, reaching the CWAs vicinity by late
Saturday night into Sunday. PoP is expected to increase Saturday
afternoon; however, guidance for this second system is generally
more northerly, suggesting the heaviest precipitation will be
concentrated north of the CWA, primarily along and north of the Ohio
River. Nonetheless, isolated light accumulations across the northern
CWA cannot be entirely ruled out through Sunday morning. A cold
surface high-pressure system will subsequently build into the region
behind the departing low, ushering in some of the coldest
temperatures 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 system toward the
end of the forecast period.

In summary, the period will be characterized by the passage of two
distinct Clipper systems, one from Thursday night into Friday and
the second Saturday night into Sunday. Both systems are forecast to
bring periods of light snow accumulation. Strong surface high
pressure will subsequently establish itself over the region on
Sunday, driving cold temperatures down to the upper single digits
and mid-teens. A notable warmup ahead of the next system is forecast
to commence by Wednesday.

&&

.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
ISSUED AT 1155 PM EST TUE DEC 9 2025

Mid and high level clouds are still currently crossing the area.
Winds have settled to generally from the south to southwest at
10 kts or less. However, winds aloft will begin to ramp up
tonight ahead of an approaching cold front. With that, a Low Level
Jet (LLJ) moves across the area tonight, leading to the threat of
LLWS for most of the night. Around 12Z, that cold front starts to
pass through producing a potential for mainly light rain for most
TAF sites between 13-18Z Wednesday along with CIGs falling to IFR
or lower by evening. Winds will remain out of the southwest with
gusts of 25-30 kts, though the threat of LLWS diminishes with the
frontal passage and more effective mix down.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
Lake Wind Advisory until 6 PM EST this evening for KYZ051-052-
060-079-080-083-084-106.

Winter Weather Advisory from 7 PM this evening to 10 AM EST
Thursday for KYZ086-087-110-113-115>117-120.

Winter Weather Advisory from 3 PM this afternoon to 10 AM EST
Thursday for KYZ088-118.


&&

$$

SHORT TERM...GEERTSON
LONG TERM...VORST
AVIATION...GREIF