949
FXUS63 KJKL 091030
AFDJKL

AREA FORECAST DISCUSSION
National Weather Service Jackson KY
530 AM EST Tue Dec 9 2025

.KEY MESSAGES...

- Mainly dry weather is expected through Tuesday night.

- Gusty southwesterly winds between 30 and 40 mph are likely on
  Wednesday.

- The pattern remains active through the end of the work week,
  although confidence remains low in each passing system`s
  precipitation type forecast.

- A much colder airmass is forecast to move into the region for
  the weekend, with widespread low temperatures in the teens
  likely.

&&

.SHORT TERM...(Today through Wednesday)
Issued at 530 AM EST TUE DEC 9 2025

Temperatures vary widely across the forecast area this morning, ranging
from the mid teens to near 20 in the far north where skies have
remained clear to the mid 20s to lower 30s farther south where a
low stratus deck has been persistent. A glance at the surface map
reveals high pressure extending from Southern Quebec tracing
southward to over the Southern Appalachians and then westward
across the Lower Mississippi Valley. A weak ~1007 mb surface low
is noted near Duluth, MN with a warm front extending southward
along the Mississippi River. A much stronger ~990 mb surface
clipper low is noted over Alberta. The latest 500 hPa weather map
shows much of the CONUS east of the Rockies under a broad trough.
An embedded vorticity max is noted near Duluth, MN, while another
vorticity max is noted over Western Canada (near the clipper low).

The warm front and its associated upper level disturbance will
sweep eastward today, crossing eastern Kentucky with little more
than a period of increased cloud cover. Meanwhile, the surface
high pressure slowly departs off the Atlantic Seaboard. A robust
~30 kt 925 mb southwesterly jet will develop behind the front.
With the diurnal heating, the mixing layer should deepen
sufficiently for mixed layer momentum transfer values of 15 to 25
kts across the area, a good proxy for peak surface wind gusts. The
pressure gradient will only tighten more tonight as the aforementioned
clipper initially over Alberta races southeast to over Lake
Michigan late tonight while deepening to ~980 mb or lower. This
will almost certainly keep mixing going overnight (or reengage
mixing shortly after sunset if boundary layer decoupling is able
to occur in some of the more sheltered valley locales). Anticipate
that winds will further increase on Wednesday as the GFS BUFKIT
soundings show mixed-layer momentum transfer increasing to 25-35+
kts with heating. Multiple rounds of light precipitation appear
probable on Wednesday; the first is a round of showery
precipitation in the morning to midday associated with a strong
vorticity lobe within the 500 hPa trough axis. The second round,
more likely to mix with snow, comes during the evening with a
strong cold front trailing behind the clipper. Soundings suggest
brief graupel is possible with any embedded convective elements,
although a switch to all snow cannot be entirely ruled out,
especially on the back edge of the quickly moving cold front.
Strong CAA follows heading into the beginning of the long-term.

In sensible weather terms, look for a cool start of the day
yielding to increasing sunshine and high temperatures rebounding
into the lower to middle 40s while the southwest breeze picks up
and becomes gusty (15 to 25 mph gusts from the southwest). For
tonight, the breeze remains gusty and may actually strengthen in
more exposed locales. Temperatures may dip back into the 30s for a
time this evening but will almost certainly rise back to near or
even well into the 40s. On Wednesday, it will become windy with
multiple rounds of showers, possibly mixed with graupel and even
some flakes. Southwest wind gusts in excess of 30 mph are probable
for most locations outside of the sheltered valley locales, most
widespread during the afternoon and evening. Temperatures peak in
the mid 40s north to near 50 south before dropping.

.LONG TERM...(Wednesday through Monday)
Issued at 447 PM EST MON DEC 8 2025

Broader troughing, with embedded progressive short wave troughs,
will be the story aloft generally east of the Rockies through the
rest of the week. The pattern will be more amplified on the front
end of the period. While the model agreement is good regarding
the long wave pattern, timing of the smaller scale features and
sensible weather details continue to be challenging to predict
with confidence. As such, have stuck closer to the blended
guidance for precipitation chances. Did make some minor
temperature adjustments for a few periods, mainly to incorporate
ridge/valley temperature differences, as well as to play up more
diurnally-limited temperature regimes, where confidence was a bit
higher regarding the cloudier and colder spells.

We start out in the middle of the week, with gusty southwest
winds. The 12z ensemble probabilities have come down just a bit
for seeing 40 mph gusts on the GFS compared to the 00z run. As
such, have maintained continuity with the previous forecast,
sticking with the 90th percentile blended guidance from later in
the morning through the early afternoon hours, when wind gusts
will peak in the 30 to 40 mph range. Wednesday will likely be the
warmest day of the week, with highs in the upper 40s to lower 50s.
Mainly rain will overspread the area from northwest to southeast
during the day, as a frontal system traverses southeast from the
Ohio Valley into the Tennessee Valley. Some upslope snow will
follow Wednesday night into early Thursday, with precipitation
chances lingering in the forecast from Thursday night through
Friday night, generally favoring locations east of I-75. Will
continue to keep precipitation types generalized to rain and/or
snow, as temperature profiles remain low confidence. A
reinforcement of colder air follows for this weekend, although
spread remains large within the ensemble envelope. Overnight lows
in the teens look probable for most valleys, especially Sunday
night, with the surface high in closer proximity. Highs will
retreat to the 30s this weekend, before recovering above 40 by
early next week.

&&

.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
ISSUED AT 1257 AM EST TUE DEC 9 2025

A low MVFR to high IFR ceiling is drifting back north of the
Mountain Parkway early this morning. This cloud deck will likely
overspread the remainder of the forecast area including SYM
over the next few hours. The ceiling is expected to begin breaking
up toward/after sunrise allowing for the return of VFR conditions
area wide. Winds will be light and variable through 12Z and then
become southwest and increase to the 5 to 12KT range on average
for the afternoon hours, remaining gusty or even increasing
Tuesday night. Winds aloft will increase late in the period. Thus
LLWS wind shear may become a threat during the last ~6 hours of
the period.

&&

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

&&

$$

SHORT TERM...GEERTSON
LONG TERM...JKL
AVIATION...GEERTSON