Decatur, IL Weather Forecast
Local 7-day forecast
Mostly Sunny
Track current conditions, temperature changes, wind, and the full daily outlook for Decatur, IL in one place.
Mostly sunny, with a high near 86. South southeast wind 3 to 7 mph.
Local Weather Overview
This forecast page for Decatur, IL is designed for quick trip planning, giving you a clean read on daytime highs, overnight lows, and changing conditions across the upcoming forecast window. Latest sync: Aug 27, 2026 6:25 PM CDT.
The active forecast window currently covers Aug 29 to Sep 2, 2026 for Decatur, IL.
Page Snapshot
- Page focus
- city weather
- Forecast window
- Aug 29 to Sep 2, 2026
- Latest sync
- Aug 27, 2026 6:25 PM CDT
- Forecast office
- ILX
- Source
- NOAA / NWS
Daily Outlook
This Week in Decatur
Tuesday looks like the warmest upcoming period in Decatur at 97 degrees F.
Saturday Night is the coolest period ahead with temperatures near 67 degrees F.
The strongest winds are forecast for Sunday at about 10 to 14 mph S.
The forecast from Aug 29 through Sep 2 stays mostly dry.
Forecast Details
- Last updated
- Aug 27, 2026 6:25 PM CDT
- Coverage
- 5 days
- Time zone
- America/Chicago
- Forecast office
- ILX
- Radar station
- KILX
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
Partly cloudy, with a low around 67. South southeast wind 6 to 9 mph.
Mostly sunny, with a high near 92. South wind 10 to 14 mph, with gusts as high as 21 mph.
Mostly clear, with a low around 72.
Mostly sunny, with a high near 95.
Partly cloudy, with a low around 75.
Sunny, with a high near 97.
Mostly clear, with a low around 75.
Mostly sunny, with a high near 96.
Mostly clear, with a low around 74.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Saturday
Aug 29
|
Mostly Sunny
|
86°F |
3 to 7 mph
SSE
|
|
Saturday Night
Aug 29
|
Partly Cloudy
|
67°F |
6 to 9 mph
SSE
|
|
Sunday
Aug 30
|
Mostly Sunny
|
92°F |
10 to 14 mph
S
|
|
Sunday Night
Aug 30
|
Mostly Clear
|
72°F |
13 mph
S
|
|
Monday
Aug 31
|
Mostly Sunny
|
95°F |
14 mph
SSW
|
|
Monday Night
Aug 31
|
Partly Cloudy
|
75°F |
10 mph
SSW
|
|
Tuesday
Sep 1
|
Sunny
|
97°F |
12 mph
SW
|
|
Tuesday Night
Sep 1
|
Mostly Clear
|
75°F |
8 mph
SSW
|
|
Wednesday
Sep 2
|
Mostly Sunny
|
96°F |
9 mph
SW
|
|
Wednesday Night
Sep 2
|
Mostly Clear
|
74°F |
7 mph
SSW
|
Nearby Forecasts
Explore weather pages for nearby cities and major places around Decatur.
