Weather StoryAlmanac, microseasons, and the day's weather story.

Weather in Illinois

Climate at a glance

Illinois covers two distinct climate zones across 1,456 cities and towns. Predominantly humid subtropical (59% of cities), with warm-summer humid continental pockets (41%).

The state spans roughly 5.5° of latitude (37.0° N to 42.5° N), from Cairo in the south to Apple River in the north. Chicago is the largest city by population.

ZoneCities%
humid subtropical85658.8%
warm-summer humid continental60041.2%

Microseason · May 16–20 · Predominantly Southeast Subtropical

Roses open on the Piedmont edge

Late spring blooms flood gardens and wild margins. Roses, azaleas, rhododendron peak. The overstory is emerald.

Read this microseason across nine climate regions → · See all 72 microseasons

Microseason content for Illinois is drawn from the Southeast Subtropical corpus (59% of the state's cities sit in this region).

All cities in Illinois

1,456 cities & towns

Weather in Illinois — All Cities & Forecasts