100
FXUS63 KJKL 020245 AAA
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
945 PM EST Mon Dec 1 2025

.KEY MESSAGES...

- A messy winter weather event is on track for tonight and
  Tuesday, with wintery precipitation on the way, especially for
  locations along and north of the Mountain Parkway.

- Drier and colder weather will be in place for the middle of the
  week. Temperatures will average between 5 and 10 degrees colder
  than normal.

- The pattern will turn active towards the weekend with additional
  chances of precipitation.

&&

.UPDATE...
Issued at 945 PM EST MON DEC 1 2025

02Z sfc analysis shows developing low pressure and its warm front
pushing into central and eastern Kentucky. This is arriving as a
slug of pcpn falling as rain in the south where wetbulbing has
already exceeded freezing. Further north, though, the drier air
and wetbulbing is making for sleet and snow approximately along
the WSW outline. Look for this to be the case initially along and
a bit south of the Mountain Parkway before the column moistens
enough to fall as rain with a healthy warm nose helping this
transition. The more complicated area is to the northwest of this
where snow and sleet, along with a potential for freezing rain,
sets in and may not ever transition to rain. This is where the
bulk of the accumulation will occur and supports the Winter
Weather Advisory. Pavement temperatures are in the mid to upper
30s most places so expect much of the initial frozen pcpn to melt
- but also contribute to cooling the roads. Anticipate slick
spots to develop by midnight in some of the untreated locations.
Currently, temperatures are running in the low to mid 30s north
and the upper 30s in the south. Meanwhile, amid light and variable
winds at the sfc, dewpoints are generally in the low and mid 30s
southwest to the low and mid 20s elsewhere. Have updated the
forecast to add in the latest obs and trends for the T/Td/Sky
grids but also to fine tune the pcpn arrival southwest to
northeast as well as p-type onset and transition through the
night. These adjustments have been sent to the NDFD and web
servers along with a freshening of the zones, WSW, SPS, and SAFs.

&&

.SHORT TERM...(This evening through Tuesday night)
Issued at 213 PM EST MON DEC 1 2025

The Winter Weather Advisory has been expanded south and southwest
given a sufficient number of mesoscale and global models
depicting strong frontogenetic forcing potential extending in
roughly an arc from parts of northeastern Kentucky southwest into
central Kentucky, mainly between around midnight tonight and the
Tuesday morning commute. Snow accumulation forecasts have likewise
been raised in these areas, while the areal extent of ice
accumulations has also expanded slightly, though maximum amounts
look to remain at or below two-tenths of an inch. Some of the
more aggressive guidance which indicate frontogenetic forcing
indicate the potential for isolated strips of up to 4 inches of
snow accumulation, with the Interstate 64 corridor and north the
more likely locations to see such potential. Note that if
frontogenetic forcing is not realized or displaced from current
forecasts, snow and ice accumulations may be significantly lower
with much less impact on travel late tonight through the Tuesday
morning commute.

Otherwise, there is no significant change to the larger-scale
forecast, with a surface cyclone developing currently over the Deep
South with an attendant surface trough extending north to the
Cumberland Plateau region west of the Appalachians. This system will
move to the East Coast Tuesday, with colder air spilling into the
region from the northwest Tuesday into Tuesday night. The latest
forecast does keep low-end PoPs (flurries and light snow showers)
longer into the afternoon and evening Tuesday within the cold
advection and upslope wind regime.

.LONG TERM...(Wednesday through Monday)
Issued at 218 PM EST MON DEC 1 2025

The long-term period opens Wednesday morning with good model
agreement. The analysis shows broad 500 hPa ridging over the
Southeast US, adjacent to an elongated ~590 dam high over the
Caribbean. There is also a large, deep sub-500 dam low centered over
Hudson Bay while another pronounced positively-tilted ridge is noted
upstream, extending from Hawaii to the Yukon Territory. A 500 hPa
trough axis extends southwest from the deep parent low over Hudson
Bay to over the Southwestern CONUS. At the surface, a broad surface
high over the Southeastern CONUS has an approximately 1023 mb core
centered over the Central and Southern Appalachians. Upstream, a
cold front is draped from the Central Plains northeastward over the
Upper Midwest and beyond to an ~995 mb surface low over southeastern
Hudson Bay. Behind that front, another ~1035 mb surface high is
noted over Saskatchewan and adjacent provinces and states.

Model differences remain relatively small through Friday morning,
lending high forecaster confidence in overall pattern evolution. The
aforementioned trough will rotate cyclonically around the upper low,
shearing away from some of the energy over the Southwestern CONUS
while dropping the associated cold front across our forecast area on
Thursday, perhaps reinforcing a baroclinic zone to our south. The
trailing area of high pressure passes over the Ohio Valley through
early Friday. Uncertainty increases substantially thereafter as
model spread increases. Southern stream energy may lead to weak
cyclogenesis along the baroclinic zone by later Friday and Friday
night, but much of the latest guidance suggests that most of this
activity remains shunted south toward the Gulf of America and
Southeast Coast. The NBM PoP was retained for this forecast period,
though it has decreased sharply since the 00Z package. It may
continue drying up, although a slight poleward shift in the 01/12Z
deterministic ECMWF brought light precipitation northwest enough to
brush southeastern KY. Another low-amplitude trough axis, rotating
around the parent 500 hPa low, dives in from the northwest this
weekend, but timing and strength across the Ohio Valley become much
less certain by that time. Moisture increases only minimally ahead
of the trough`s associated cold front, perhaps attended by a weak
low-pressure wave, and the details regarding precipitation type and
amount are unclear at this point. The forecast becomes even more
obscure next week, though the general model consensus suggests at
least modest reamplification of the upper-level troughing over the
Eastern CONUS.

In sensible weather terms, look for generally below-normal
temperatures and precipitation through the long-term forecast
period. Wednesday may end up being the sunniest day of the period
and one of the mildest with highs mainly in the upper 30s north to
mid 40s south. Clouds increase heading into Thursday but expect
little more than a sprinkle or flurry. It will be colder, however,
with Thursdays highs only forecast to reach the mid 30s north to low
40s south. For Friday through the weekend, there will likely be
ample clouds, generally thinner to the north, mixed with filtered
sunshine at times. Daily high temperatures should rebound into the
40s for the weekend, though they will likely cool off heading into
the new work week. Nighttime lows should range mainly in the 20s and
30s, likely coldest Thursday night and warmest Friday and Saturday
nights. There are some precipitation chances from Friday through
early next week, but any amounts appear minimal at this time.

&&

.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
ISSUED AT 645 PM EST MON DEC 1 2025

VFR conditions were noted across eastern Kentucky, under
increasing and thickening clouds. Precipitation will overtake the
area from the south and west through 06Z, with conditions
deteriorating to IFR or worse into dawn, Tuesday. The
precipitation is expected to be rain for most of the forecast area
tonight, except for a wintery mix north of the Mountain Parkway.
Conditions then improve from northwest to southeast toward
Tuesday afternoon, but models differ on the timing of the end of
precipitation as well as how quickly conditions improve. Winds
will be light and variable through the bulk of the period.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 10 AM EST Tuesday for KYZ044-
050>052-058>060-068-069-104-106-108.


&&

$$

UPDATE...GREIF
SHORT TERM...CMC
LONG TERM...GEERTSON
AVIATION...CMC/GREIF