Williamson, IL Weather Forecast
Local 7-day forecast
Showers And Thunderstorms Likely
Track current conditions, temperature changes, wind, and the full daily outlook for Williamson, IL in one place.
Showers and thunderstorms likely. Partly sunny, with a high near 80. Chance of precipitation is 70%.
Local Weather Overview
This forecast page for Williamson, 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 11, 2026 11:18 PM CDT.
The active forecast window currently covers Apr 16 to Apr 18, 2026 for Williamson, IL.
Page Snapshot
- Page focus
- city weather
- Forecast window
- Apr 16 to Apr 18, 2026
- Latest sync
- Apr 11, 2026 11:18 PM CDT
- Forecast office
- LSX
- Source
- NOAA / NWS
Daily Outlook
This Week in Williamson
Friday looks like the warmest upcoming period in Williamson at 83 degrees F.
Friday Night is the coolest period ahead with temperatures near 54 degrees F.
The strongest winds are forecast for Friday at about 6 to 15 mph S.
Precipitation is mentioned in 5 upcoming forecast periods.
Forecast Details
- Last updated
- Apr 11, 2026 11:18 PM CDT
- Coverage
- 3 days
- Time zone
- America/Chicago
- Forecast office
- LSX
- Radar station
- KLSX
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
A chance of showers and thunderstorms. Mostly clear, with a low around 59. Chance of precipitation is 40%.
A slight chance of rain showers before 1pm, then a chance of showers and thunderstorms. Mostly sunny, with a high near 83. Chance of precipitation is 40%.
Showers and thunderstorms likely. Mostly cloudy, with a low around 54. Chance of precipitation is 60%.
Showers and thunderstorms likely. Mostly cloudy, with a high near 67. Chance of precipitation is 60%.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Thursday
Apr 16
|
Showers And Thunderstorms Likely
|
80°F |
7 to 10 mph
SW
|
|
Thursday Night
Apr 16
|
Chance Showers And Thunderstorms
|
59°F |
8 mph
S
|
|
Friday
Apr 17
|
Chance Showers And Thunderstorms
|
83°F |
6 to 15 mph
S
|
|
Friday Night
Apr 17
|
Showers And Thunderstorms Likely
|
54°F |
13 mph
SW
|
|
Saturday
Apr 18
|
Showers And Thunderstorms Likely
|
67°F |
12 to 15 mph
NW
|
Nearby Forecasts
Explore weather pages for nearby cities and major places around Williamson.