801
FXUS63 KILX 102042
AFDILX

Area Forecast Discussion
National Weather Service Lincoln IL
242 PM CST Wed Dec 10 2025

.KEY MESSAGES...

- Snow will spread across much of central Illinois Thursday
  afternoon through Thursday night. There is a 50-80% chance for
  greater than 2 inches of snow along and northeast of a Macomb to
  Robinson line, with a 20-40% chance for greater than 4 inches of
  snow along I-74.

- Another surge of very cold air is expected by the end of the
  week...resulting in sub-zero apparent temperatures Friday night
  through Monday morning.

&&

.SHORT TERM...  (Tonight Through Late Thursday Night)
Issued at 241 PM CST Wed Dec 10 2025

Light snow, with little to no accumulations, will linger across
northern areas of the CWA this evening, mainly along and north of
I-74. Then, after a brief dry period, Thursday morning, a stronger
clipper system will plunge into the area for Thursday afternoon
through Thursday night. All models have trended southwest of I-74 with
the axis of the heaviest snow band; however, the NAM keeps it
along I-74. Blend of models also shifts the axis southwest and
this trend was followed for this forecast package. Typical with
many clippers, decent warm air advection ahead of the system will
provide ample moisture to work with and there will be sufficient
isentropic lift along and north of the low track; which should
result in decent amount of snowfall across most of central IL,
with the heaviest snowfall occurring Thur evening. Snow should
begin in the west Thur afternoon with 1-2 inches possible by 6pm
northwest of I-55. Snow will continue to the east and southeast
with 2-3 inches possible during the evening hours across areas
north of a Macomb to Robinson line. If the forecast track remains
the same through tonights models, then a winter weather advisory
is likely for tomorrow afternoon through tomorrow night. There
appears to be a 50-80% chance of amounts being over 2 inches, with
even a 20-40% chance of amounts exceeding 4 inches along I-74. The
probabilities could increase, as long as models remain consistent
the next 12 hours.

P-type will primarily be snow. However, forecast soundings
southwest of Springfield and south of Effingham show small
possibilities of brief periods of rain or freezing rain mixing
with the snow during the late afternoon or early evening. Do to
the high uncertainty and low probability of the freezing rain
occurring, will not have it in the forecast at this time.

Temperatures will remain below freezing through tomorrow night, across
all areas except for southeast IL.

Auten

.LONG TERM...  (Friday through Next Wednesday)
Issued at 241 PM CST Wed Dec 10 2025

Another clipper system will quickly push through Saturday, which
could lay down another 2-3 inches of snow. However, the bigger
concern will be the extremely cold temperatures for the weekend.
Coldest temperatures will be Saturday night and Sunday night, with
air temperatures below zero across most of the CWA. Combined with
the winds and wind chills of 15 to 25 below zero will be common
Sat night, with wind chills around 15 below for Sun night.
Fortunately, dry weather is expected Sunday through the beginning
of next week. The other good news is the bitter cold temps will be
short lived as temperatures will begin to significantly warm with
temps reaching above freezing on Tuesday and in the 40s for by
Wednesday.

Auten

&&

.AVIATION...  (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1153 AM CST Wed Dec 10 2025

MVFR cloud conditions will continue for the balance of the next 18
hours of the TAF period. A band of snow showers will depart
 to the east of the terminal sites by 20z, with CMI the remaining
site to get the snow band. However, radar returns have shown a
weakening trend for the snowfall bands and vis drops will likely
remain above IFR. A few flurries possible out of the MVFR deck
this afternoon. Otherwise, gusty winds will be the main concern
this afternoon, with W-NW gusts to 30 KT lingering but diminishing
as evening approaches. NAM/HRRR forecast soundings continue to show
the MVFR cloud deck persisting through Thursday morning. Winds
speeds by mid-evening should drop to 12kt or less after 03z/04z,
so we kept that trend going. Ceilings tomorrow morning are
projected to increase to VFR before the end of this TAF period.

Shimon

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$