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Hazardous Weather Conditions
Current conditions at
St. Louis Regional Airport (KALN)
Lat: 38.89°NLon: 90.03°WElev: 518ft.
Fair
N/A
| Humidity | NA |
| Wind Speed | Calm |
| Barometer | 30.08 in |
| Dewpoint | N/A |
| Visibility | 10.00 mi |
| Last update | 3 Jul 5:55 am CDT |
Extended Forecast for
Alton IL
Extreme Heat Warning July 3, 06:15am until July 4, 08:00pm
NOW until 8:00pm Sat
Extreme Heat Warning
Today
High: 95 °F
Sunny then
Slight Chance
T-stormsTonight

Low: 75 °F
Partly Cloudy
Independence Day
High: 93 °F
Sunny then
Slight Chance
T-stormsSaturday Night
Low: 73 °F
Slight Chance
T-storms then
Chance
T-stormsSunday

High: 90 °F
Chance
T-stormsSunday Night

Low: 71 °F
Chance
T-stormsMonday

High: 88 °F
Slight Chance
T-stormsMonday Night

Low: 70 °F
Partly Cloudy
Detailed Forecast
Today
A 20 percent chance of showers and thunderstorms after 1pm. Sunny, with a high near 95. Heat index values as high as 103. Calm wind becoming south 5 to 8 mph in the morning.
Tonight
Partly cloudy, with a low around 75. South wind 5 to 7 mph becoming calm in the evening.
Independence Day
A 20 percent chance of showers and thunderstorms after 3pm. Mostly sunny, with a high near 93. Heat index values as high as 103. Calm wind becoming southwest 5 to 7 mph in the morning.
Saturday Night
A slight chance of showers and thunderstorms before 10pm, then a chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 73. South wind around 5 mph becoming calm in the evening. Chance of precipitation is 50%.
Sunday
A 40 percent chance of showers and thunderstorms, mainly after 1pm. Partly sunny, with a high near 90. Calm wind becoming northwest around 6 mph in the morning.
Sunday Night
A 40 percent chance of showers and thunderstorms, mainly before 1am. Partly cloudy, with a low around 71.
Monday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 88.
Monday Night
Partly cloudy, with a low around 70.
Tuesday
Mostly sunny, with a high near 88.
Tuesday Night
Mostly clear, with a low around 70.
Wednesday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 90.
Wednesday Night
Partly cloudy, with a low around 72.
Thursday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 91.
Additional Forecasts and Information
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ABOUT THIS FORECAST
Point Forecast:
Alton IL
38.91°N 90.16°W (Elev. 505 ft)
38.91°N 90.16°W (Elev. 505 ft)
5:51 am CDT Jul 3, 2026
6am CDT Jul 3, 2026-6pm CDT Jul 9, 2026



