872
FXUS63 KILX 101951
AFDILX

Area Forecast Discussion
National Weather Service Lincoln IL
251 PM CDT Thu Jul 10 2025

.KEY MESSAGES...

- Daily chances for afternoon/evening thunderstorms will be seen
  through the weekend with the highest chances being on Friday
  and Saturday.

- Hot and humid conditions will be in place through the end of
  this week and again early next week. Temperatures look to trend
  cooler by the end of next week.

&&

.DISCUSSION...
Issued at 251 PM CDT Thu Jul 10 2025

...Daily Storm Chances Through the Weekend...

A few widely scattered showers and storms have developed in east-
central Illinois along a remnant outflow boundary from an overnight
thunderstorm complex. Further northwest, a MCV from the same storm
complex is spinning over southeast Minnesota/northeast Iowa and
will be the focus for thunderstorm development over the northern
half of Illinois going into this evening. Although most guidance
keeps the majority of this activity north of our local area, a few
outlier solutions do show storms stretching as far south as I-72.
Increasing shear with the approaching MCV and moderately strong
instability could lead to a few organized storms capable of mainly
strong winds and heavy rainfall.

A low-level jet will nose into northern IL overnight, leading to
repeated rounds of heavy rainfall north of the area. Better
chances for precipitation arrive later on Friday here locally as a
shortwave impulse ahead of a parent trough spreads into the
middle Mississippi Valley Friday afternoon. A warm front is
expected to lift into north- central parts of the state by evening
with hot and humid conditions developing south of the front.
Instability will become moderately strong by afternoon with
SBCAPEs looking to approach or exceed 2000 J/kg. ~30 kt of
effective wind shear, especially near the front, will be
sufficient for thunderstorm organization, posing a risk for all
severe hazards. Storms look to fire up sometime late Friday
afternoon or early evening in our west, with activity spreading
east into the nighttime hours.

A cold front moving through the area on Saturday will bring
additional chances for precipitation through the weekend. The better
upper forcing will be displaced north of the area, though hot and
humid conditions and increasing wind shear with the front will once
again lead to marginal parameters for a few stronger thunderstorms
Saturday afternoon and evening.

Predictability becomes less certain going into next week, though a
brief break in precipitation appears possible early in the week as
an upper ridge moves overhead. Upper troughing looks to swing back
through the northern CONUS by midweek, which could lead to
additional precipitation chances later in the week.

...Hot and Humid Through the End of the Week, Again Early Next Week..

Despite daily precipitation chances, temperatures will remain hot
and humid through the end of this week with high temperatures on
Friday peaking in the low to middle 90s paired with heat indices
around 100, give or take a few degrees. Temperatures fall slightly
over the weekend with the cold front passage, but will quickly
rebound by the beginning of next week as an upper ridge slides
through the Midwest states.

Temperatures by the end of next week into next weekend look to trend
somewhat cooler than normal with the Climate Prediction Center`s 8-
14 day temperature outlook (Jul 17-23) highlighting a 33-50% chance
for below normal temperatures.

NMA

&&

.AVIATION...  (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1247 PM CDT Thu Jul 10 2025

VFR conditions and light south-southwest winds will continue
through most of the TAF period. A mesoscale system will work
through northern Illinois later today, sparking the development of
scattered storms later this afternoon into the evening. Most of
this activity looks to largely stay north of the terminals,
however some of the latest guidance does show a few isolated
storms coming close to northern airfields (KPIA, KBMI). PROB30
groups are mentioned at these locations between 21-00Z to cover
this small chance. Winds pick up some by late tomorrow morning
with speeds around 10 kts or so. Better chances for thunderstorms
come later Friday afternoon into the evening hours.

NMA

&&

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

$$