How reliable is this forecast?

Forecasts for the first 3 days are usually highly accurate; this page is updated about every 30 minutes.

Weather · United States

Illinois 3-Day Weather Forecast

Over the 3 days from October 17 to October 19, temperatures in Illinois will range from 3°C to 20°C; the warmest day is October 19. No significant rain is expected during this period.

Illinois 3-day forecast table

The bar shows each day's range against the period's lowest and highest temperature.

Illinois weather hour by hour

The line shows temperature, bars show chance of rain.

Frequently asked questions

What will the weather be like in Illinois over the next 3 days?: Over the 3 days from October 17 to October 19, temperatures in Illinois will range from 3°C to 20°C; the warmest day is October 19. No significant rain is expected during this period.
How reliable is this forecast?: Forecasts for the first 3 days are usually highly accurate; this page is updated about every 30 minutes.