Grand Detour, IL Weather Forecast
Local 7-day forecast
Sunny
Track current conditions, temperature changes, wind, and the full daily outlook for Grand Detour, IL in one place.
Sunny, with a high near 76.
Local Weather Overview
This forecast page for Grand Detour, 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: Apr 18, 2026 12:26 PM CDT.
The active forecast window currently covers Apr 22 to Apr 24, 2026 for Grand Detour, IL.
Page Snapshot
- Page focus
- city weather
- Forecast window
- Apr 22 to Apr 24, 2026
- Latest sync
- Apr 18, 2026 12:26 PM CDT
- Forecast office
- LOT
- Source
- NOAA / NWS
Daily Outlook
This Week in Grand Detour
Thursday looks like the warmest upcoming period in Grand Detour at 80 degrees F.
Friday Night is the coolest period ahead with temperatures near 44 degrees F.
The strongest winds are forecast for Thursday at about 10 to 15 mph S.
Precipitation is mentioned in 4 upcoming forecast periods.
Forecast Details
- Last updated
- Apr 18, 2026 12:26 PM CDT
- Coverage
- 3 days
- Time zone
- America/Chicago
- Forecast office
- LOT
- Radar station
- KDVN
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
Mostly clear, with a low around 56.
A slight chance of rain showers after 1pm. Mostly sunny, with a high near 80.
A slight chance of rain showers before 7pm, then showers and thunderstorms likely. Mostly cloudy, with a low around 59.
Showers and thunderstorms likely. Mostly cloudy, with a high near 71.
A chance of showers and thunderstorms. Mostly cloudy, with a low around 44.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Wednesday
Apr 22
|
Sunny
|
76°F |
5 to 10 mph
ESE
|
|
Wednesday Night
Apr 22
|
Mostly Clear
|
56°F |
5 to 10 mph
SE
|
|
Thursday
Apr 23
|
Mostly Sunny then Slight Chance Rain Showers
|
80°F |
10 to 15 mph
S
|
|
Thursday Night
Apr 23
|
Showers And Thunderstorms Likely
|
59°F |
15 mph
S
|
|
Friday
Apr 24
|
Showers And Thunderstorms Likely
|
71°F |
10 to 15 mph
SSW
|
|
Friday Night
Apr 24
|
Chance Showers And Thunderstorms
|
44°F |
10 to 15 mph
W
|
Nearby Forecasts
Explore weather pages for nearby cities and major places around Grand Detour.
