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Alton, MO Weather Forecast
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Alton Weather Forecast
| OVERNIGHT | LABOR DAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | WEDNESDAY NIGHT | THURSDAY | THURSDAY NIGHT | FRIDAY | FRIDAY NIGHT | SATURDAY |
 |  |  | | | |  |  | | |  | |
| Partly Cloudy | Sunny | Clear | Sunny | Mostly Clear | Sunny | Chance of T-Storm | Chance of T-Storm | Chance of T-Storm | Chance of T-Storm | Chance of Showers | Chance of T-Storm |
| Lo: 69°FLo: 21°C | Hi: 95°FHi: 35°C | Lo: 61°FLo: 16°C | Hi: 99°FHi: 37°C | Lo: 69°FLo: 21°C | Hi: 100°FHi: 38°C | Lo: 70°FLo: 21°C | Hi: 90°FHi: 32°C | Hi: 91°FHi: 33°C Lo: 61°FLo: 16°C | Hi: 91°FHi: 33°C Lo: 61°FLo: 16°C | Lo: 65°FLo: 18°C | Hi: 91°FHi: 33°C |
| POP: 50% | POP: 80% | POP: 20% | POP: 20% | POP: 20% | POP: 20% |
POP = Probability of Precipitation.
Weather Outlook Updated: 943 PM CDT Sun Sep 06 2026 
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Issued: 539 PM CDT Sun Sep 6 2026
Key Messages
- An Extreme Heat Warning remains in effect for entire area through this evening. The warning has been extended through Monday evening for counties west of Highway 65. Maximum afternoon heat index values around 105+.
- Scattered showers and thunderstorms this afternoon and evening. An isolated strong to severe thunderstorm, capable of producing damaging wind gusts of 50 to 70 mph.
- Hot and dry conditions are worsening drought and increasing fire danger. Above average temperatures are like...