Champaign, Illinois 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

061
FXUS63 KILX 180546
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
1146 PM CST Fri Jan 17 2025

.KEY MESSAGES...

- Rain will move in tonight ahead of a cold frontal passage,
  which will also usher in much colder temperatures behind it. A
  brief change to snow is likely before precipitation ends, which
  could result in a dusting of snow, possibly exceeding an inch
  from I-57 eastward and I-70 northward.

- Wind chills below minus 10 degrees are likely at times Sunday
  morning to Wednesday morning. There is high confidence (40-90%
  chance) in these extreme cold values.

&&

.UPDATE...
Issued at 911 PM CST Fri Jan 17 2025

Based on radar data and new HiRes model data, the rain is mainly
across eastern and southeastern Illinois this evening...and will
likely remain in those areas overnight. Have trimmed pops in the
west and central parts of the CWA, west of the Illinois river.
Still kept a chance in some areas, but higher pops will be in the
east and southeast. Still think colder air will move in behind the
precip and change some of the precip into snow before it ends.
Adjustments to pops/wx did not change that thinking in the
forecast. Remainder of the forecast looks fine and updated
forecast should already be out.

Auten

&&

.DISCUSSION...
Issued at 304 PM CST Fri Jan 17 2025

An upper level shortwave currently centered over Oklahoma will
eject east-northeastward through southern IL tonight, spreading
rain into central and especially southeast IL this evening as an
arctic cold front rapidly surges southeastward into the area,
catching up with the precipitation as it comes to an end by
Saturday morning. This should change precipitation over to snow
for at least a brief time. Current estimates from several high-res
models depict up to a couple of hours of snow over east-central
IL before ending, which could result in over an inch of snow from
roughly I-57 eastward and I-70 northward.

Temperatures will be dropping rapidly behind the front,
and struggle to rise much during the day Saturday. Expect daytime
temperatures ranging from low 20s near Galesburg to low 30s at
Lawrenceville Saturday, before temperatures plummet to single digits
north of I-72 and teens south of I-72 Sunday morning. With brisk
northwest winds continuing, wind chills will be approaching -15
around Galesburg and below zero values over most of central IL. The
risk of wind chills dipping below -10 areawide (-15 from around I-74
northward) begins Sunday night and continues at times until Tuesday
night. Current ensembles indicate probabilities ranging from around
40 to 60 percent of exceeding advisory criteria (-15 from I-72
counties northward, -10 to the south). Moderation of temperatures is
expected late in the week, although still remaining slightly below
normal. Chances for precipitation look paltry, although with a
relatively persistent cyclonic flow over the region, it wouldn`t
be surprising to see some occasional snow flurries.

37

&&

.AVIATION...  (For the 06z TAFs through 06z Saturday Night)
Issued at 1146 PM CST Fri Jan 17 2025

VFR conditions will prevail at all sites, except DEC and CMI,
next 24hrs. DEC and CMI will still see rain and possible mix of
rain and snow for several hours overnight. Both should be done
with the precip by 10-11z. Then VFR for both sites the rest of the
TAF period. Cigs through most of the TAF period with be around
5-6kft with cigs around 3.5kft at CMI and DEC when the precip is
around. Believe all sites will scatter out in the evening with
only scattered cirrus expected from afternoon at PIA to the
evening at DEC and CMI. Winds will be southwest for most sites,
but PIA had already switched for northwest. BMI, SPI, DEC, and CMI
will see winds become northwest during the night and then closer
to northerly this afternoon and into the evening. Wind speeds will
be less than 10kts at PIA, BMI and SPI, with DEC and CMI still
breezy with gusts round 20kts. All sites will see an increase of
wind speeds with gusts of 23-26kts during the daytime hours. In
the evening, gusts will reduce and speeds will be around 10-15kts.


Auten

&&

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

$$