Home / Local Weather & Traffic / Illinois / Decatur / Weather Forecast

Decatur, IL Weather Tomorrow

Get a closer look at tomorrow's weather in Decatur and the upcoming 5 day forecast with precipitation probability, daily and nightly weather conditions, high and low temperature trends, sunrise and sunset information, sky cover, wind speed, wind direction, and wind chill across the Decatur area.
Updated: Wed Sep 9th 2026 1:45 PM CDT
Decatur, IL Weather – 9-9 – Sunny
87° / 71°
Sunny
Daytime highs will reach 87°F with lows dropping to 71°F in Decatur, where bright and sunny conditions. Rainfall predicted to have a 71% chance with an estimated 0.27in. Wind will be moderate, blowing around 16mph on average and gusts of 17.7mph at 8 PM. The humidity will be on the higher side, averaging about 74%, the maximum being 94% at 6 PM and 57% being its lowest at 3 PM. Barometric pressure is its highest of 30.01inHg at 8 PM, a lowest point of 29.97inHg at 4 PM with an avg 29.99inHg.
Decatur, IL Weather – 9-10 – Light Rain Shower
74° / 67°

Weather Tomorrow

Light Rain Shower
In Decatur, periods of rain are likely with highs near 74°F and lows around 67°F. The chance of rain is 90% with an estimated 0.67in. Wind will be moderate, blowing around 12mph on average and gusts of 26mph at 1 AM. High humidity with average of 91% is anticipated, the maximum being 98% at 1 AM and 72% being its lowest at 5 PM. Barometric pressure is its highest of 30.02inHg at 1 AM, a lowest point of 29.94inHg at 5 PM with an avg 29.99inHg.
Decatur, IL Weather – 9-11 – Overcast
82° / 64°
Overcast
Highs will reach 82°F with lows near 64°F in Decatur, where cloud-filled skies are. There might be light rainfall having a 14% chance. Winds will be light at 9mph and gusts of 19.2mph at 5 PM. The humidity will be on the higher side, averaging about 77%, the maximum being 98% at 6 AM and 46% being its lowest at 4 PM. Barometric pressure is its highest of 30.01inHg at 8 AM, a lowest point of 29.88inHg at 8 PM with an avg 29.96inHg.
Decatur, IL Weather – 9-12 – Sunny
89° / 67°
Sunny
In Decatur, bright and sunny conditions with highs near 89°F and lows around 67°F. There's a very small chance of rainfall, only about 6%. Winds will be light at 9mph and gusts of 17.9mph at 1 PM. The humidity will be on the higher side, averaging about 66%, the maximum being 96% at 7 AM and 31% being its lowest at 4 PM. Barometric pressure is its highest of 29.94inHg at 11 AM, a lowest point of 29.87inHg at 7 PM with an avg 29.91inHg.
Decatur, IL Weather – 9-13 – Overcast
90° / 70°
Overcast
Highs will reach 90°F with lows near 70°F in Decatur, where cloud-filled skies are. There might be light rainfall having a 11% chance. Winds will be light at 9mph and gusts of 16.6mph at 11 PM. The humidity will be on the higher side, averaging about 67%, the maximum being 93% at 4 AM and 33% being its lowest at 4 PM. Barometric pressure is its highest of 30.02inHg at 10 AM, a lowest point of 29.94inHg at 12 AM with an avg 29.98inHg.
Decatur, IL Weather – 9-14 – Sunny
95° / 72°
Sunny
In Decatur, bright and sunny conditions with highs near 95°F and lows around 72°F. Rainfall predicted to have a 57% chance with an estimated 0.06in. Wind will be moderate, blowing around 15mph on average and gusts of 28mph at 10 PM. The humidity will be on the higher side, averaging about 61%, the maximum being 88% at 7 AM and 34% being its lowest at 4 PM. Barometric pressure is its highest of 30inHg at 12 AM, a lowest point of 29.87inHg at 6 PM with an avg 29.94inHg.

Currently

Patchy Light Drizzle 81°F
30.01 inHg.
Barometer
67%
Humidity
NNW 5.8 mph
Wind
Patchy Light Drizzle

5 Day Forecast Nearby

More Local Information

Bookmark and Share

Get the LocalConditions.com App on Google Play
Sign up for a membership to go Ad free