558
FXUS63 KILX 021754
AFDILX

Area Forecast Discussion...Updated Aviation
National Weather Service Lincoln IL
1154 AM CST Mon Feb 2 2026

.KEY MESSAGES...

- Another round of snow is possible late Monday night into Tuesday
  (20-50% chance, highest south of I-72). In most areas, any
  accumulations will be minor (less than 1") but there could be a
  narrow band that produces a few inches of snow somewhere south
  of a Jacksonville to Paris line.

- Temperatures will be less cold this week and through the
  weekend, with highs generally in the 20s and 30s. A more
  noticeable warm-up is possible next week (40-50% chance).

&&

.DISCUSSION...
Issued at 230 AM CST Mon Feb 2 2026

*** TODAY ***

The primary concern through early this morning is the potential
for patchy freezing drizzle, mainly near/north of I-74. Had noted
a few days ago that forecast soundings suggested a loss of cloud
ice as our Sunday snow event came to an end, and it appears that
has come to fruition. Regional radar imagery shows areas of very
weak returns ahead of a front that is approaching from the
northwest. Ceilings were generally above 2500 feet earlier Sun
evening, which is high for drizzle to reach the sfc, and HRRR
forecast soundings showed a shallow layer of dry low-level air
that would mitigate the drizzle potential. However, ceilings have
trended steadily lower at Galesburg (KGBG), with the 08z/2am
observation reporting 800 foot ceilings. Have not seen sfc
observations report DZ or UP south of I- 80, and have not received
any reports of surfaces become slick locally, so have held off on
issuing a Special Weather Statement at this time. I don`t feel
strongly that we`ll see any freezing drizzle, but felt the
situation warranted at least a mention of patchy freezing drizzle
in the gridded forecast (near/north of I- 74). The drizzle
potential will end as the front moves through and swings winds
around to northwesterly. Based on the projected timing of the
front, this means the freezing drizzle concerns could linger into
the morning commute for locations like Champaign-Urbana and
Danville. Be on the lookout for sneaky slick spots.

Once that front moves through this morning, central IL will be
situated near the saddle point between surrounding sfc highs/lows.
Winds stay northwesterly, but will be relatively light (generally
around or less than 10 mph). Skies stay mostly cloudy, with highs
near freezing.

*** TONIGHT - TUESDAY ***

A shortwave located over Montana early Monday morning will provide
another chance for snow to the ILX CWA late tonight into Tues. Models
highlight a swath of light snow across IA/north- central IL
overnight as the wave digs toward the area. Introduced some slight
chance (20%) PoPs near/north of I-74 to account for this. Within
this swath, only a few tenths of snow accumulation are forecast.

The more challenging aspect of the forecast still revolves around
the sfc low that tracks south of the I-70 (Missouri) and I-64
(Illinois) corridors on Tues. Exactly how far north and west
precip extends remains a point of uncertainty, with some models
showing no precip in the ILX CWA and others depicting a banded
snow event. The 00z NAM was the most bullish, with forecast cross
sections still depicting a crosshair signature (strong ascent
within the dendritic growth zone) which leads to a narrow stripe
of 2-3" of snow. This east-west oriented band could form as far
northwest as Jacksonville, although its worth noting the
00z NAM is a significant outlier compared to the rest of the
deterministic guidance.

The uncertainties around the placement of this potential narrow
snow band make it a challenging system to effectively message.
Made adjustments to the forecast to start increasing PoPs and QPF,
but our gridded forecast still calls for less than 1" of snow
area- wide. The probabilistic NBM has just a 20-40% chance for
over 1" of snow in areas from Mattoon-to- Paris and southeastward,
quickly increasing to over 50% in south- central IN. Do not be
surprised if the are seemingly drastic adjustments to the forecast
between now and its arrival. There is still icy precip potential
with this system, but that potential has consistently been focused
just south of the ILX CWA, and snow should be the primary p-type
in our area. Any precip should exit by 00z Wed/6pm Tues.

*** WEDNESDAY AND BEYOND ***

A weak sfc high will be present Tue night and Wed night. Cloud
cover will play a substantial role on the low temps those nights.
For now, guidance suggests more cloud cover south of I-70 Tues
night, keeping lows in the teens, while north of I-70 lows fall to
near 10 degF. On Wed night, clouds are more likely across west-
central IL in response to low-level WAA associated with a clipper
developing well to the north. This again results in a forecast of
lows in the teens in the cloud covered areas (west of I-55), and
lows in the single digits in the (mostly) clear sky areas (east of
I-55).

Mostly dry conditions are favored through the weekend. That
aforementioned clipper is still on track to move through the upper
Midwest late in the week, but it should track far enough north to
keep precip just north of the ILX CWA. As southerly flow picks up
ahead of this wave, highs on Thurs could reach the upper 30s
across west-central IL (cooler to the east). The NBM has highs
climbing to near 40 on Fri, although with a strong, dry cold
frontal passage during the day Fri I do start to question whether
we might have non- diurnal temperature trends on Fri. Either way,
the winds on Thurs/Fri will be strong enough that wind chill
values struggle to rise above freezing, so it won`t exactly be a
robust warm up.

Following the Fri frontal passage, a cooler air mass (not extreme
cold) moves in for Sat. A more appreciable warm-up appears
possible into next week, with CPC highlighting a 40-50% chance of
above normal temps. Normal temps for that week of Feb feature
highs in the upper 30s and lows near 20. The NBM indicates a
30-50% chance of highs above 50 each day Mon-Thurs (Feb 9-12).

Erwin

&&

.AVIATION...  (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 1151 AM CST Mon Feb 2 2026

MVFR ceilings prevail across central IL late Monday morning,
though periods of VFR have been observed at SPI and areas further
south where ceilings are higher and near the 3kft threshold. Added
a tempo group to each of the the I-72 airfields to account for
the potential category-crossing ceiling fluctuations over the next
several hours. HREF suggests medium-high confidence (80% chance)
these ceilings will break up by sunset, though additional lower
ceilings and even some flurries could sink into the region again
early Tuesday morning.

Bumgardner

&&

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

$$