Round Lake

Sweet Grass County, Illinois, United States

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Current Weather

18°

Overcast

Feels Like:

Min: 17°

Max: 22°

The next few hours will be overcast, with today reaching 22°C and dropping to 11°C. The coming days will be drizzle

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Hourly Forecast

18° 20° 20° 20° 22° 22° 22° 21° 21° 20° 19° 18° 18° 17° 17° 17° 17° 14° 13° 12° 11° 11° 11° 11°
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7pm
8pm
9pm
10pm
11pm
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Today
Tomorrow

Daylight Hours

06:39

Sunrise

18:53

Sunset

12 hours 13 minutes of sunlight today

Moon

Waxing Crescent

12:41

Moonrise

20:52

Moonset

Daily Forecast

Today

17°
22°

Thursday

10°
20°

Friday

10°
21°

Saturday

18°

Sunday

20°

Monday

21°

Tuesday

22°

Wednesday

22°

Thursday

11°
22°

Friday

15°
23°

Air Quality Data Available

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UV Index

No protection needed
0 Low
Low Extreme

Humidity

81% Humid
Low High

Weather in Round Lake today, September 16, 2026

Expect a muted, overcast feel in Round Lake on September 16, 2026 as cloud persists. Brighter breaks, if they arrive, should stay brief. Cloud leads the morning, peaking close to 100% near 09:00. Sunshine has little room until later in the day.

The day peaks near 22°C and cools toward 17°C. Moisture in the air spans 68%-82%, with the highest values around 08:00. Airflow remains manageable, reaching about 4.7 km/h around 09:00.

Through the afternoon cloud remains the main feature, with cover near 100% around 12:00. Bright spells should stay limited even as the day wears on. Horizontal visibility holds close to 16.1 km. Daylight runs from 06:39 to 18:53, lasting 12 hours 13 minutes of sunlight today.

Taken together, overcast skies in Round Lake on September 16, 2026 favour indoor or covered options, with temperatures near 22°C.

Frequently asked questions about weather in Round Lake

How warm does it get in Round Lake?

The warmest month in Round Lake is July, with average high temperatures of 27°C. The average temperature during this period is around 23°C.

How cold does it get in Round Lake?

The coldest month in Round Lake is January, with average low temperatures of -6°C. The average temperature during this period is around -3°C.

What is the wettest time of year in Round Lake?

The wettest month in Round Lake is May, with an average of 122mm of precipitation.

What is the driest time of year in Round Lake?

The driest month in Round Lake is February, with an average of 55mm of precipitation.

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Metric (°C, km/h)