Local weather forecast

Weather in Glen Carbon, IL

Updated 2026-08-11 12:45 local time · ZIP codes 62034

Sunny
Now91°F

Sunny

High / Low102° / 77°
Rain chance3%
Wind13 mph
Weather alerts

Active alerts

1
Extreme Heat Warning issued August 11 at 2:17AM CDT until August 12 at 8:00PM CDT by NWS St Louis MO

* WHAT...Dangerously hot conditions with heat index values up to 111. * WHERE...Portions of south central and southwest Illinois and central and east central Missouri. * WHEN...Until 8 PM CDT Wednesday. * IMPACTS...Heat related illnesses increase significantly during extreme heat and high humidity events.

Safety instructions

Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances. Take extra precautions if you work or spend time outside. When possible reschedule strenuous activities to early morning or evening. Know the signs and symptoms of heat exhaustion and heat stroke. Wear lightweight and loose fitting clothing when possible. To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 9 1 1. People in the Saint Louis Metropolitan Area can get information about cooling centers or energy assistance related to the excessive heat by calling the United Way of Greater Saint Louis at 800-427-4626, or if calling from a land line phone dial 2-1-1. You can also call Cool Down Saint Louis at 314-241-7668.

Hourly

Next hours

NowSunny91°2% rain
2 PMSunny102°1% rain
3 PMSunny101°1% rain
4 PMSunny101°1% rain
5 PMSunny100°1% rain
6 PMSunny98°1% rain
7 PMSunny93°2% rain
8 PMClear88°2% rain
9 PMClear86°3% rain
10 PMClear84°3% rain
11 PMClear83°4% rain
12 AMClear80°4% rain
Forecast

3-day weather forecast

Today2026-08-11
Sunny
102° 77°Sunny
Rain 3%Gust 13 mph
Tomorrow2026-08-12
Sunny
96° 79°Sunny
Rain 4%Gust 10 mph
Thursday2026-08-13
Sunny
100° 73°Sunny
Rain 57%Gust 14 mph
Conditions

Weather details

Feels like99°F
Humidity56%
Pressure29.97 inHg
Visibility6 mi
Wind13 mph SW
Wind gusts16 mph
Precipitation0.00 in
UV index7
Daylight

Sunrise, sunset and moon

Sunrise06:10 AM
Sunset07:59 PM
Moonrise04:13 AM
Moon phaseNew Moon
Practical guide

Weather insights for today

Umbrella not essential

Rain chance stays relatively low over the next 12 hours (up to 4%).

Choose light, breathable clothing

It feels like 99°F with winds near 13 mph.

Best window: 8 PM

88°F, 2% rain chance and 6 mph wind.

Driving conditions look generally normal

Visibility is around 6 mi; gusts may reach 17 mph.

Running conditions are less comfortable

Current temperature is 91°F, wind 13 mph, rain chance up to 4%.

High UV protection needed

UV index is 7. Sunscreen, shade and protective clothing are recommended.

Glen Carbon weather today

Sunny and 91°F in Glen Carbon, IL. Today's high is 102°F with a 3% rain chance. Winds are around 13 mph with gusts near 16 mph. Relative humidity is 56%, pressure is 29.97 inHg, and visibility is about 6 miles.

Tonight and tomorrow in Glen Carbon

Sunrise is at 06:10 AM and sunset is at 07:59 PM. Tomorrow's forecast calls for Sunny with a high near 96°F and a low near 79°F. The maximum rain chance is 4%.

Nearby

Weather near Glen Carbon

Illinois

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