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Alton, IL

101°F
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Alton

Illinois

101°
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Alton, IL Weather
Today WinterCast Local {stormName} Tracker Hourly 10-Day Radar MinuteCast® Monthly Air Quality Health & Activities

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6 PM

98°
RealFeel® 103°
Very Hot
RealFeel Guide
Very Hot
101° to 107°
Caution advised. Danger of dehydration, heat stroke, heat exhaustion and heat cramps if outside for extended periods, and especially while doing strenuous activities.
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rain drop 0%
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Mostly sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™101°

Heat Index106°

WindSSW 7 mph

Air QualityFair

Max UV Index1.3 (Low)

Wind Gusts9 mph

Humidity40%

Indoor Humidity40% (Very Humid)

Dew Point70° F

AccuLumen Brightness Index™8 (Bright)

Cloud Cover12%

Visibility10 mi

Cloud Ceiling33300 ft

7 PM

95°
RealFeel® 99°
Hot
RealFeel Guide
Hot
90° to 100°
Caution advised. Possible danger of dehydration, heat stroke, heat exhaustion and heat cramps if outside for extended periods, and especially while doing strenuous activities.
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rain drop 0%
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Mostly sunny
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

RealFeel Shade™99°

Heat Index102°

WindSSW 7 mph

Air QualityFair

Max UV Index0.4 (Low)

Wind Gusts7 mph

Humidity46%

Indoor Humidity46% (Very Humid)

Dew Point71° F

AccuLumen Brightness Index™2 (Dark)

Cloud Cover11%

Visibility10 mi

Cloud Ceiling30000 ft

8 PM

92°
RealFeel® 96°
Hot
RealFeel Guide
Hot
90° to 100°
Caution advised. Possible danger of dehydration, heat stroke, heat exhaustion and heat cramps if outside for extended periods, and especially while doing strenuous activities.
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rain drop 0%
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Clear
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

Heat Index99°

WindS 7 mph

Air QualityFair

Wind Gusts9 mph

Humidity53%

Indoor Humidity53% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover5%

Visibility10 mi

Cloud Ceiling30000 ft

9 PM

88°
RealFeel® 93°
Hot
RealFeel Guide
Hot
90° to 100°
Caution advised. Possible danger of dehydration, heat stroke, heat exhaustion and heat cramps if outside for extended periods, and especially while doing strenuous activities.
LEARN MORE
rain drop 0%
Chevron down
Clear
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

Heat Index95°

WindSSE 6 mph

Air QualityFair

Wind Gusts12 mph

Humidity59%

Indoor Humidity59% (Extremely Humid)

Dew Point72° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover2%

Visibility10 mi

Cloud Ceiling30000 ft

10 PM

85°
RealFeel® 90°
Hot
RealFeel Guide
Hot
90° to 100°
Caution advised. Possible danger of dehydration, heat stroke, heat exhaustion and heat cramps if outside for extended periods, and especially while doing strenuous activities.
LEARN MORE
rain drop 0%
Chevron down
Clear
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

Heat Index91°

WindSSE 6 mph

Air QualityFair

Wind Gusts10 mph

Humidity66%

Indoor Humidity66% (Extremely Humid)

Dew Point73° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover2%

Visibility10 mi

Cloud Ceiling30000 ft

11 PM

82°
RealFeel® 87°
Very Warm
RealFeel Guide
Very Warm
82° to 89°
Older adults, infants, and those with sensitive medical conditions should minimize outdoor activity, especially in the sunshine.
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rain drop 0%
Chevron down
Clear
alerts

Extreme Heat Warning

12:12 AM Thursday - 8:00 PM Saturday

Heat Index86°

WindSSE 6 mph

Air QualityFair

Wind Gusts9 mph

Humidity74%

Indoor Humidity74% (Extremely Humid)

Dew Point73° F

AccuLumen Brightness Index™0 (Dark)

Cloud Cover5%

Visibility10 mi

Cloud Ceiling30000 ft

Hourly Weather Forecast for Alton

AccuWeather's hourly forecast for Alton provides hour-by-hour temperatures, RealFeel® Temperature, and precipitation probability through the next 10 days. The current hour shows 98° with a RealFeel® of 103°, mostly sunny with a 0% chance of precipitation. Each hourly forecast includes wind speed, humidity, air quality, UV index, and the AccuLumen Brightness Index™, AccuWeather's measure of perceived outdoor light intensity. Forecasts are generated by proprietary systems developed by AccuWeather meteorologists since 1962.

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World North America United States Illinois Alton

Weather Near Alton:

  • O'Fallon, MO
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