495
FXUS63 KILX 092044
AFDILX

Area Forecast Discussion
National Weather Service Lincoln IL
244 PM CST Tue Dec 9 2025

.KEY MESSAGES...

- Strong northwesterly winds gusting 40-50 mph will accompany
  scattered snow showers Wednesday morning. Be prepared for sudden
  drops in visibility if driving.

- Snowfall is anticipated from Thursday night into Friday morning,
  with a 20-40% chance of greater than 2 inches of snow along and
  north of a Macomb to Robinson line.

- Very cold air will affect central Illinois this weekend, with a
  50% chance of sub-zero wind chills north of I-72/Danville
  Saturday morning. Wind chill temperatures will be even colder on
  Sunday morning.

&&

.DISCUSSION...
Issued at 244 PM CST Tue Dec 9 2025

Temperatures have warmed above freezing this afternoon throughout
central Illinois, with wet bulb temperatures anticipated to
support rain at the surface when precipitation begins this evening
in association with a low moving southeast across Minnesota and
into southern Wisconsin. The greatest coverage of rain should be
just ahead of the low pressure trough as it moves across the area
late tonight. Of greater impact will be the west/northwest winds
behind the surface trough, continuing as a cold front moves
through Wednesday morning. Wind speeds at the top of the mixed
layer are around 50 knots, and we anticipate that any convective
elements which may develop ahead of the cold front may enhance
wind gust speeds. We`ve issued a Wind Advisory for much of the
forecast area from midnight to noon. Snow showers potentially
developing near the cold front Wednesday morning could be
responsible for rapid drops in visibility when combined with the
strong winds. With not much accumulation anticipated, the sudden
visibility changes will likely be the primary impact from any
snow.

Attention then turns to our next clipper system due to arrive in
the Thursday night/Friday morning time frame. With a cold
thermodynamic profile and lift peaking in the dendritic growth
zone, this could be an efficient snowfall producer despite its
quick movement. Snowfall may be maximized just north of the low
where the greatest precip residence time is. Amounts observed with
a fast-moving high SLR event like this will probably be highly
sensitive to the track of the low, with 90th percentile amounts
along the northern edge of the forecast area being around 4
inches.

Cold air returns in earnest this weekend, with a ~1040 mb high
moving out of south-central Canada into the Midwest. Though wind
speeds at the leading edge of this high are not forecast to be
extreme, it doesn`t take much wind to bring wind chills down
substantially. The coldest wind chills are anticipated on Sunday
morning, with most likely values ranging from 10 to 20 degrees
below zero. In addition, some light snow is anticipated along the
baroclinic zone at the leading edge of the high Saturday, with a
30-50% chance of greater than 1 inch of snow north of
I-72/Danville.

AAT

&&

.AVIATION...  (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1200 AM CST Tue Dec 9 2025

A strong low pressure system in the Dakotas will track southeast
across southern Minnesota, Wisconsin, and into southwest Lower
Michigan tonight, bringing active weather to central Illinois.
Conditions will remain VFR through most or all of the overnight
period, though scattered showers may impact the terminals this
evening (highest chances at PIA, BMI, and CMI). Southwest winds
will gust sporadically over 25 kt this evening into the overnight
period, but when they will become much stronger when they switch
over to a west-northwesterly direction between 09 and 12z;
frequent 30-40 kt gusts are expected, with localized gusts to 50
kt with any snow showers that form along the secondary cold front
during the 10-15z time frame. Those winds will veer to a north-
northwesterly direction and gradually ease after roughly 16-17z,
but MVFR ceilings (arriving with the cold front between 09 and
12z) should persist through the afternoon.

Bumgardner

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from midnight tonight to noon CST Wednesday for
ILZ027>031-036>038-040>045-047>056-061-062-066.

&&

$$