Alton, IL Weather Forecast
Local 7-day forecast
Sunny
Track current conditions, temperature changes, wind, and the full daily outlook for Alton, IL in one place.
Sunny, with a high near 88. West wind 0 to 5 mph.
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: Oct 10, 2026 9:04 AM CDT.
The active forecast window currently covers Oct 11 to Oct 16, 2026 for Alton, IL.
Page Snapshot
- Page focus
- city weather
- Forecast window
- Oct 11 to Oct 16, 2026
- Latest sync
- Oct 10, 2026 9:04 AM CDT
- Forecast office
- LSX
- Source
- NOAA / NWS
Daily Outlook
This Week in Alton
Columbus Day looks like the warmest upcoming period in Alton at 95 degrees F.
Friday Night is the coolest period ahead with temperatures near 46 degrees F.
The strongest winds are forecast for Friday at about 12 to 17 mph NW.
Precipitation is mentioned in 7 upcoming forecast periods.
Forecast Details
- Last updated
- Oct 10, 2026 9:04 AM CDT
- Coverage
- 6 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
Mostly clear, with a low around 64. South wind around 5 mph.
Sunny, with a high near 95. Southwest wind 5 to 13 mph.
Mostly clear, with a low around 71.
Sunny, with a high near 92.
A slight chance of showers and thunderstorms between 7pm and 1am, then a chance of showers and thunderstorms. Mostly clear, with a low around 64. Chance of precipitation is 40%.
Showers and thunderstorms likely. Mostly sunny, with a high near 81. Chance of precipitation is 60%.
Showers and thunderstorms likely. Mostly cloudy, with a low around 60. Chance of precipitation is 60%.
A chance of showers and thunderstorms. Partly sunny, with a high near 80. Chance of precipitation is 50%.
A chance of showers and thunderstorms. Partly cloudy, with a low around 54. Chance of precipitation is 40%.
A slight chance of rain showers. Mostly sunny, with a high near 71. Chance of precipitation is 20%.
A slight chance of rain showers before 7pm. Partly cloudy, with a low around 46. Chance of precipitation is 20%.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Sunday
Oct 11
|
Sunny
|
88°F |
0 to 5 mph
W
|
|
Sunday Night
Oct 11
|
Mostly Clear
|
64°F |
5 mph
S
|
|
Columbus Day
Oct 12
|
Sunny
|
95°F |
5 to 13 mph
SW
|
|
Monday Night
Oct 12
|
Mostly Clear
|
71°F |
10 mph
SW
|
|
Tuesday
Oct 13
|
Sunny
|
92°F |
10 mph
W
|
|
Tuesday Night
Oct 13
|
Slight Chance Showers And Thunderstorms
|
64°F |
7 mph
NE
|
|
Wednesday
Oct 14
|
Showers And Thunderstorms Likely
|
81°F |
6 to 10 mph
E
|
|
Wednesday Night
Oct 14
|
Showers And Thunderstorms Likely
|
60°F |
10 mph
E
|
|
Thursday
Oct 15
|
Chance Showers And Thunderstorms
|
80°F |
12 mph
S
|
|
Thursday Night
Oct 15
|
Chance Showers And Thunderstorms
|
54°F |
8 to 12 mph
W
|
|
Friday
Oct 16
|
Slight Chance Rain Showers
|
71°F |
12 to 17 mph
NW
|
|
Friday Night
Oct 16
|
Slight Chance Rain Showers then Partly Cloudy
|
46°F |
10 to 16 mph
NW
|
Nearby Forecasts
Explore weather pages for nearby cities and major places around Alton.
