Alton, IL Weather Forecast
Local 7-day forecast
Chance Showers And Thunderstorms
Track current conditions, temperature changes, wind, and the full daily outlook for Alton, IL in one place.
A chance of showers and thunderstorms. Partly sunny, with a high near 90. West wind around 6 mph. Chance of precipitation is 50%.
Local Weather Overview
This forecast page for Alton, 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: Jul 8, 2026 2:54 PM CDT.
The active forecast window currently covers Jul 10 to Jul 14, 2026 for Alton, IL.
Page Snapshot
- Page focus
- city weather
- Forecast window
- Jul 10 to Jul 14, 2026
- Latest sync
- Jul 8, 2026 2:54 PM CDT
- Forecast office
- LSX
- Source
- NOAA / NWS
Daily Outlook
This Week in Alton
Tuesday looks like the warmest upcoming period in Alton at 92 degrees F.
Sunday Night is the coolest period ahead with temperatures near 70 degrees F.
The strongest winds are forecast for Sunday at about 3 to 9 mph NE.
Precipitation is mentioned in 6 upcoming forecast periods.
Forecast Details
- Last updated
- Jul 8, 2026 2:54 PM CDT
- Coverage
- 5 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
Showers and thunderstorms likely. Mostly cloudy, with a low around 72. Chance of precipitation is 70%.
Showers and thunderstorms likely. Partly sunny, with a high near 88. Chance of precipitation is 70%.
A chance of showers and thunderstorms. Partly cloudy, with a low around 71. Chance of precipitation is 50%.
A chance of showers and thunderstorms. Mostly sunny, with a high near 88. Chance of precipitation is 30%.
A slight chance of showers and thunderstorms before 7pm. Partly cloudy, with a low around 70. Chance of precipitation is 20%.
Sunny, with a high near 90.
Mostly clear, with a low around 72.
Sunny, with a high near 92.
Mostly clear, with a low around 74.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Friday
Jul 10
|
Chance Showers And Thunderstorms
|
90°F |
6 mph
W
|
|
Friday Night
Jul 10
|
Showers And Thunderstorms Likely
|
72°F |
1 to 6 mph
SW
|
|
Saturday
Jul 11
|
Showers And Thunderstorms Likely
|
88°F |
3 to 7 mph
W
|
|
Saturday Night
Jul 11
|
Chance Showers And Thunderstorms
|
71°F |
2 to 7 mph
N
|
|
Sunday
Jul 12
|
Chance Showers And Thunderstorms
|
88°F |
3 to 9 mph
NE
|
|
Sunday Night
Jul 12
|
Slight Chance Showers And Thunderstorms then Partly Cloudy
|
70°F |
1 to 9 mph
NE
|
|
Monday
Jul 13
|
Sunny
|
90°F |
2 to 8 mph
NE
|
|
Monday Night
Jul 13
|
Mostly Clear
|
72°F |
1 to 8 mph
NE
|
|
Tuesday
Jul 14
|
Sunny
|
92°F |
2 to 6 mph
N
|
|
Tuesday Night
Jul 14
|
Mostly Clear
|
74°F |
2 to 6 mph
S
|
Nearby Forecasts
Explore weather pages for nearby cities and major places around Alton.
