Area Forecast Discussion
Issued by NWS Louisville, KY

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
530
FXUS63 KLMK 032347
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
647 PM EST Wed Dec 3 2025

.KEY MESSAGES...

* Brief light snow or flurries late tonight into Thursday morning
  across southern IN and northern KY. No accumulation to a few
  tenths of an inch will be possible.

* Thursday night into Friday morning, a system will move south of
  the region and bring mixed precip and snow to southern Kentucky.
  Confidence is increasing a light accumulations and significant
  accumulations are not expected.

* Messy weather pattern will continue through mid next week, where
  light precip will be possible.

&&

.SHORT TERM /THROUGH THURSDAY/...
Issued at 249 PM EST Wed Dec 3 2025

Moisture concentrations below 925mb are currently observed in model
forecasts and area soundings, sustaining a layer of low stratus
clouds over the lower Ohio Valley. At this time, a clearing trend is
noted, progressing from the southeast toward the northwest. The
eastern and southern portions of the region are anticipated to
experience several hours of predominantly clear skies, while the
remainder of the area will observe at least partly cloudy
conditions. Given the current sky cover and the limited duration of
insolation following cloud dissipation, maximum temperatures are
expected to remain near or below the freezing point.

Tonight, a shortwave trough will traverse the region, accompanied by
an advancing cold front. A 3035 kt LLJ, coupled with a mid and
upper-level jet, will create a favorable jet structure to induce
atmospheric lift despite minimal available moisture. Consequently,
the possibility of flurries exists across the entire area, and light
snowfall is forecast for southern Indiana and northern Kentucky
during the early morning hours. Impactful accumulation is not
anticipated; rather, amounts are expected to range from a trace up
to a few tenths of an inch. With light winds and low-level moisture,
the development of very patchy freezing fog is possible, although
its extent may be limited by the overcast conditions associated with
the frontal passage. Overnight low temperatures are forecast to be
in the mid-20s.

High pressure will subsequently build in behind the cold front and
become centered over the northern Ohio Valley. This pattern will
establish a prevailing drier northerly and northwesterly surface
flow on Thursday. The low stratus layer will begin to exit the
region Thursday morning, from the northwest to the southeast. CAA is
expected to prevent high temperatures from rising above freezing
across most of the region.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
Issued at 249 PM EST Wed Dec 3 2025

===== Thursday - Friday =====

Flow aloft is expected to become more zonal during this period,
introducing a contiguous stream of vorticity across the region. A
weak trough will traverse the area on Friday, displacing surface
high pressure to the east. This weak trough will introduce a low-
pressure system over the Southeastern CONUS. The lower Ohio Valley
will reside on the northern periphery of this system, situated
within a zone of frontogenesis. Furthermore, a weak LLJ will
contribute to lift, interacting with limited low-level moisture.
This setup is conducive to producing snowfall across southern and
eastern Kentucky from Thursday night into Friday.

With the forecast now within the range of Hi-Res guidance, the
expected snowfall accumulation ranges from a Trace to a few tenths
of an inch. Isolated areas in the Lake Cumberland region could
potentially observe amounts approaching 0.5 inches. The GFS
continues to indicate less snowfall, while the Euro presents a more
aggressive solution. Examination of the EFI reveals elevated
probabilities and a shift-of-tails signal over southern Kentucky.
Considering the early stage of the season, this shift-of-tails
signal is not a significant concern; however, it warrants continued
monitoring, particularly regarding the Friday morning commute.


===== Weekend - Next Week =====

A disorganized, predominantly zonal flow aloft will persist across
the region, where minor atmospheric disturbances may traverse the
area and yield light precipitation. Despite the unorganized nature
of the pattern, it will remain transient, resulting in intermittent
light precipitation while largely maintaining dry conditions.

A more significant trough is projected to move through on Monday,
increasing the probability of mixed rain and snow showers. Ensemble
and deterministic guidance indicate considerable variability in
potential outcomes, but this system could bring a few tenths of an
inch of snowfall. By the middle of the week, temperatures are
expected to moderate to near-normal values, reaching the upper 40s
and lower 50s.

&&

.AVIATION /00Z TAFS THROUGH 06Z FRIDAY/...
Issued at 646 PM EST Wed Dec 3 2025

This afternoon, IFR stratus has cleared out at BWG and RGA, with LEX
right on the edge of the stratus at this hour. Over the next few
hours, stratus may retreat to the north a bit more, but then it is
expected to expand back to the southeast later tonight as a cold
front moves across the region. Along the front, IFR ceilings,
possibly LIFR, and reduced visibilities from mist are expected.
Winds will also veer from SW to NW, though speeds should generally
remain less than 6 kt through sunrise Thursday. Confidence in timing
of the return of the lower flight categories is medium. Behind the
front, a band of light snow will approach HNB/SDF/LEX after 08Z,
though confidence is decreasing that snow will reach SDF/LEX.

Behind the cold front, CIGs should very gradually lift Thursday
morning from north to south, with winds continuing to veer around to
the N/NE. There is a chance that HNB/SDF/LEX could break out of the
low stratus by the end of the current TAF period, but confidence in
this is still fairly low.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...None.
IN...None.

&&

$$

SHORT TERM...SRW
LONG TERM...SRW
AVIATION...CSG