Weather
Central Illinois Fall Starts Cool, Warms by Friday
Springfield, Illinois – Fall begins Tuesday with highs from 63 to 73 degrees across central Illinois before warmer air pushes temperatures toward the upper 70s.
By Miles Carter · 2026-09-22T08:51:19.241Z
Springfield, Illinois – Fall begins Tuesday with highs from 63 to 73 degrees across central Illinois before warmer air pushes temperatures toward the upper 70s.
According to the National Weather Service in Lincoln, an upper level low moving into northern Illinois Tuesday will bring a chance of a few light showers, particularly near the Illinois River Valley. The precipitation chance is 20% Tuesday, with less than a 10% chance Tuesday night.
Most of the region should then enter an extended stretch of dry weather. Wednesday will bring highs of 67 to 71 degrees, followed by 69 to 77 Thursday and 70 to 77 Friday. Saturday highs are expected to range from 68 to 77.
That means the first several days of astronomical fall will trend warmer rather than progressively colder across central Illinois.
Overnight temperatures will provide more of an autumn feel. Lows Tuesday night will range from 51 to 59 degrees, followed by 53 to 58 Wednesday night and 53 to 57 Thursday night.
The coolest night shown in the Weather Service outlook arrives Friday night, when temperatures could fall to between 47 and 53 degrees. Saturday night lows rebound slightly to 51 to 56.
The Weather Service expects an approaching warm front to bring the next meaningful chance for precipitation during the weekend. Its outlook shows a 20% rain chance Saturday night, while daytime precipitation chances Wednesday through Saturday remain at 10% or less.
For Tuesday, residents near the Illinois River Valley should keep light rain in mind for outdoor plans and travel. Elsewhere, the transition into fall will be defined more by cool temperatures than significant rain.
After Tuesday's cooler start, central Illinois should warm through Friday before precipitation chances begin increasing again over the weekend.