Cass County, IL Weather Forecast
County weather hub
Chance Showers And Thunderstorms then Sunny
Compare major city weather across Cass County, scan the latest forecast snapshots, and jump into local 7-day outlook pages from one hub.
A chance of showers and thunderstorms before 7am. Sunny, with a high near 89. South wind 12 to 21 mph, with gusts as high as 29 mph. Chance of precipitation is 30%.
County Weather Overview
This county weather page brings together forecast coverage for Cass County so visitors can compare temperatures, wind, and conditions across the region without hopping between unrelated pages.
Current forecast coverage spans 2 of 2 mapped cities in Cass County.
Page Snapshot
- Page focus
- county weather
- Forecast window
- May 17 to May 21, 2026
- Latest sync
- May 15, 2026 4:12 PM CDT
- Forecast office
- ILX
- Source
- NOAA / NWS
Daily Outlook
This Week in Cass County
Sunday looks like the warmest upcoming period in Cass County at 89 degrees F.
Wednesday Night is the coolest period ahead with temperatures near 50 degrees F.
The strongest winds are forecast for Monday at about 16 to 22 mph S.
Precipitation is mentioned in 6 upcoming forecast periods.
Forecast Details
- Last updated
- May 15, 2026 4:12 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
Mostly clear, with a low around 67. South wind 16 to 20 mph, with gusts as high as 29 mph.
Showers and thunderstorms likely after 7am. Partly sunny, with a high near 89. South wind 16 to 22 mph, with gusts as high as 33 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.
Showers and thunderstorms likely before 7pm, then showers and thunderstorms likely. Partly cloudy, with a low around 67. Chance of precipitation is 60%.
Showers and thunderstorms likely. Partly sunny, with a high near 80. Chance of precipitation is 70%.
Showers and thunderstorms likely. Mostly cloudy, with a low around 55.
A slight chance of rain showers before 7am. Mostly sunny, with a high near 70.
Mostly cloudy, with a low around 50.
Mostly sunny, with a high near 73.
Partly cloudy, with a low around 52.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Sunday
May 17
|
Chance Showers And Thunderstorms then Sunny
|
89°F |
12 to 21 mph
S
|
|
Sunday Night
May 17
|
Mostly Clear
|
67°F |
16 to 20 mph
S
|
|
Monday
May 18
|
Showers And Thunderstorms Likely
|
89°F |
16 to 22 mph
S
|
|
Monday Night
May 18
|
Showers And Thunderstorms Likely
|
67°F |
17 to 21 mph
S
|
|
Tuesday
May 19
|
Showers And Thunderstorms Likely
|
80°F |
14 to 20 mph
SW
|
|
Tuesday Night
May 19
|
Showers And Thunderstorms Likely
|
55°F |
8 to 12 mph
NW
|
|
Wednesday
May 20
|
Slight Chance Rain Showers then Mostly Sunny
|
70°F |
10 mph
N
|
|
Wednesday Night
May 20
|
Mostly Cloudy
|
50°F |
8 mph
NNE
|
|
Thursday
May 21
|
Mostly Sunny
|
73°F |
9 mph
ENE
|
|
Thursday Night
May 21
|
Partly Cloudy
|
52°F |
8 mph
E
|
Major City Forecasts
Live forecast snapshots for major cities across Cass County.
Coverage
Forecast coverage currently spans 2 of 2 mapped cities in Cass County.
Largest mapped city population in this region: 5,335.
