820
FXUS63 KILX 240457
AFDILX

Area Forecast Discussion
National Weather Service Lincoln IL
1157 PM CDT Thu Jul 23 2026

.KEY MESSAGES...

- There is a low to medium (30-50%) chance of light rain Friday
  into Friday night.

- Dangerous heat builds Sunday through Tuesday, with peak
  afternoon heat indices of 100 to 110 degrees.

- Isolated severe storms are possible late Sunday through Monday
  night, though forecast certainty remains low.

&&

.DISCUSSION...
Issued at 154 PM CDT Thu Jul 23 2026

Surface analysis shows high pressure centered over the lower Great
Lakes Region, which has resulted in a brief period of seasonally
cool weather. Temperatures early this afternoon are sitting in the
middle 70s with dewpoints in the low 50s. Similar conditions are
expected on Friday, though southerly return flow will advect
moisture back northward later in the day as the surface high pushes
off to our east.

An upper shortwave will track from the Central Plains into the Ohio
Valley region through Friday night, bringing increased cloudiness
beginning tonight. Scattered chances for rain return late Friday
morning into Friday night as the shortwave works across southwest
parts of the area. Activity will be working against somewhat drier
air initially, likely resulting in virga or sprinkles at the onset
with total QPF looking to be on the order of a few tenths of an
inch. Light rain chances may linger into Saturday morning as a weak
shortwave glides along a warm/stationary front positioned just to
our south.

Upper ridging becomes amplified over the western US by the weekend,
resulting in mid-level height rises here locally. Temperatures will
warm back into the 80s on Saturday then surge into the 90s by
Sunday. Similar temperatures will stick around through Tuesday for
some with the Extreme Forecast Index showing values of 0.9-1,
indicating that there is high confidence in an anomalous event.
This paired with dewpoints in the 70s will lead to heat indices
peaking between 100 and 110 degrees each afternoon. Heat
headlines will likely be coordinated in the coming days.

Outside of the heat, isolated chances for severe storms exist late
Sunday into Monday night as several shortwave impulses glide
along the eastern periphery of a strong upper ridge. A highly
unstable and moderately sheared airmass will be in place ahead
of the upper waves. If storms manage to initiate, severe hazards
and heavy rainfall will be likely. However, forecast certainty
remains low until mesoscale features become clearer.

Temperatures will cool back to near typical summertime values behind
of cold front by the middle of next week. The CPC 8-14 day outlook
favors near to slightly above normal temperatures and below normal
precipitation for the end of July/beginning of August.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1157 PM CDT Thu Jul 23 2026

VFR conditions expected the next 24 hours, with ceilings
gradually lowering on Friday though still well above 5,000 feet.
While a few showers are possible by late afternoon, dry air will
result in considerable uncertainty as to their existence, so no
mention will be included at this time.

&&

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

&&

$$

KEY MESSAGES...NMA
DISCUSSION...NMA
AVIATION...Geelhart