243
FXUS63 KILX 011124
AFDILX

Area Forecast Discussion
National Weather Service Lincoln IL
624 AM CDT Tue Sep 1 2026

.KEY MESSAGES...

- Afternoon Heat Index values between 100 and 105+ degrees are
  expected today through Thursday. Heat indices and may also
  reach that level on Friday and Saturday afternoon if
  convection chances hold off. A Heat Advisory is in effect over
  central and southeast IL today through Thursday afternoon.

- High temperatures in the 90s through Saturday, will lower a
  bit into the upper 80s and lower 90s early next week. The
  passing cold front brings a low (20-30%) chance of showers and
  thunderstorms Friday through Sunday morning.

&&

.DISCUSSION...
Issued at 345 AM CDT Tue Sep 1 2026

The main weather story this week will be the late season heat
wave with strong 594-596 decameter 500 mb high over the TN
river valley and into central/southern IL during mid week. Will
likely see afternoon heat indices peak from 100-105F through
much of the week with 20-40% chance of seeing heat indices peak
above 105F today through Friday. Highs in the mid to upper 90s
today through Fri with areas from Springfield to Robinson sw
near 100F. Springfield already reached 97F yesterday and only 2
degrees from the record high of 99F. We posted record highs in
the climate section below for today through Thu. We continued
the heat advisory across CWA today through Thu afternoon, but
may need to be extended it into Friday or even Saturday if
convection holds off and have less cloud cover.

A frontal boundary meandering over parts of Iowa and WI into
Thu to keep IL in the warm sector with hot humid tropical air
mass staying in place. Convection chances appear to stay north
of I-80 through Wed night, then have 20-40% pops over northern
IL just north of CWA on Thu as a short wave trof passes by to our
north. SPC Day3 Outlook has marginal risk of severe storms for wind
and hail for late Thu/Thu night ne of a Canton to Lincoln to Terre
Haute line. We have good instability Thu afternoon/evening, though
best forcing and bulk shear will be ne of CWA. We have slight chance
of convection Friday into Saturday, mainly over ne CWA and eastern
IL. A shortwave trough move eastward across the upper MS river
valley and into the Great Lakes region Wednesday night and Thursday,
though the brunt of its convection appears to pass north of central
IL. A stronger short wave moves se across the Midwest and IL during
this holiday weekend as strong mid/upper level ridge retrogrades
back into the Great Plains, putting IL in a NW upper level flow
regime. A backdoor cold front could slip through central IL by
Sunday and may bring 20-30% chance of convection from Friday through
Sunday morning (highest pops Sat night). Hot temperatures in the 90s
expected through Saturday, to cool a bit into the upper 80s/lower
90s early next week though still a good 10 degrees warmer than
normal.

The Climate Prediction Center (CPC) 8-14 Day Outlook for Sep
8-14th 50-55% chance of above normal temperatures over
central/southeast IL with precipitation trending near normal.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 623 AM CDT Tue Sep 1 2026

VFR conditions will prevail at all TAF sites next 24 hours.
Only clouds expected next 24 hours are high few cirrus. Winds
will be out of the southwest through the period. Wind speeds
will be 10kts or less during the day and then lighten a few
knots this evening.

&&

.CLIMATE...
Issued at 440 PM CDT Mon Aug 31 2026

Record high temperatures this week:

Location         Tue 9/1     Wed 9/2     Thu 9/3
========         ========    ========    ========
Bloomington      102/1894    101/2011    102/1913
Champaign        102/2011    101/2011     99/2011
Charleston        99/2011    103/1953    100/1925
Danville         101/1953    101/1953     99/1913
Decatur          102/1953    102/1953    102/1913
Jacksonville     103/1913    103/2011    101/2011
Lincoln          102/1953    101/1953    100/1913
Olney            105/1953    106/1953    105/1925
Paris            101/1953    102/1953    101/1913
Peoria           101/1913    100/1913     99/1913
Springfield      102/2011    101/2011    100/2011

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 7 PM CDT Thursday for ILZ027>029-036-037-
040>044-047>056-061>063-066>068-071>073.
Heat Advisory from 1 PM this afternoon to 7 PM CDT Thursday
for ILZ030-031-038-045-046-057.

&&

$$

KEY MESSAGES...07
DISCUSSION...07
AVIATION...Auten
CLIMATE...07/Geelhart