Collinsville

Sully County, Illinois, United States

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Current Weather

25°

Misty

Feels Like: 10°

Min: 24°

Max: 34°

The next few hours will be overcast, with today reaching 34°C and dropping to 13°C. The coming days will be drizzle

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Hourly Forecast

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Today
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Daylight Hours

06:48

Sunrise

18:59

Sunset

12 hours 11 minutes of sunlight today

Moon

Waxing Crescent

12:35

Moonrise

21:12

Moonset

Daily Forecast

Today

24°
34°

Thursday

11°
25°

Friday

10°
18°

Saturday

18°

Sunday

18°

Monday

18°

Tuesday

17°

Wednesday

18°

Thursday

35°

Friday

16°
26°

Air Quality Data Available

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UV Index

No protection needed
1 Low
Low Extreme

Humidity

84% Humid
Low High

Weather in Collinsville today, September 16, 2026

Collinsville looks cloudy on September 16, 2026, with grey skies for much of the day. Sunshine stays limited, so the overall tone is muted from the morning onward. The morning sky stays heavily clouded, with cover near 100% around 08:00. Grey conditions set the early tone before any later change.

The temperature range runs from about 24°C up to 34°C. Expect humidity between 48% and 91%, most humid near 23:00. Expect gentle winds, highest near 19:00 at 4.5 km/h.

Expect persistent cloud later on, with amounts around 100% by 12:00. Sunshine remains the exception, not the rule. Visibility stays generally good near 14.2 km on average, though it can drop toward 1.4 km in thicker cloud or showers. Sunrise is at 06:48 and sunset at 18:59, giving 12 hours 11 minutes of sunlight today.

In short, cloud leads the story in Collinsville on September 16, 2026; expect limited sun and a peak around 34°C.

Frequently asked questions about weather in Collinsville

How warm does it get in Collinsville?

The warmest month in Collinsville is July, with average high temperatures of 31°C. The average temperature during this period is around 26°C.

How cold does it get in Collinsville?

The coldest month in Collinsville is January, with average low temperatures of -3°C. The average temperature during this period is around 0°C.

What is the wettest time of year in Collinsville?

The wettest month in Collinsville is April, with an average of 140mm of precipitation.

What is the driest time of year in Collinsville?

The driest month in Collinsville is December, with an average of 63mm of precipitation.

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