Waterloo

Waukesha County, Illinois, United States

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Current Weather

28°

Partly Cloudy

Feels Like: 25°

Min: 24°

Max: 35°

The next few hours will be partly cloudy, with today reaching 35°C and dropping to 25°C. The coming days will be drizzle

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Hourly Forecast

26° 29° 31° 32° 34° 35° 34° 34° 33° 32° 31° 30° 29° 28° 28° 27° 27° 27° 26° 26° 26° 25° 25° 25°
24%
24%
24%
54%
54%
8am
9am
10am
11am
12pm
1pm
2pm
3pm
4pm
5pm
6pm
7pm
8pm
9pm
10pm
11pm
12am
1am
2am
3am
4am
5am
6am
7am
Today
Tomorrow

Daylight Hours

06:48

Sunrise

19:00

Sunset

12 hours 11 minutes of sunlight today

Moon

Waxing Crescent

12:35

Moonrise

21:14

Moonset

Daily Forecast

Today

24°
35°

Thursday

25°
35°

Friday

24°
35°

Saturday

23°
37°

Sunday

22°
35°

Monday

22°
33°

Tuesday

21°
28°

Wednesday

18°
30°

Thursday

21°
35°

Friday

16°
27°

Air Quality Data Available

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UV Index

No protection needed
1 Low
Low Extreme

Humidity

69% Comfortable
Low High

Weather in Waterloo today, September 16, 2026

Waterloo starts September 16, 2026 looking damp, with rain in the forecast and wetter spells likely at times. Waterproof kit is the safer call for early plans. Expect a grey start, with morning cloud around 61% by 08:00. Outdoor plans early on should not rely on bright skies.

Temperatures climb from an overnight low near 24°C toward a daytime high of about 35°C. Moisture in the air spans 43%-76%, with the highest values around 08:00. Expect gentle winds, highest near 23:00 at 2.5 km/h.

The second half of the day still looks unsettled, with rain probability around 54% by 17:00. Dense cloud near 73% at 19:00 keeps the feel grey. Expect visibility around 16.1 km. Sunrise is at 06:48 and sunset at 19:00, giving 12 hours 11 minutes of sunlight today.

In short, treat September 16, 2026 in Waterloo as a damp day: pack covers, watch the wetter hours, and expect a high near 35°C.

Frequently asked questions about weather in Waterloo

How warm does it get in Waterloo?

The warmest month in Waterloo is July, with average high temperatures of 32°C. The average temperature during this period is around 26°C.

How cold does it get in Waterloo?

The coldest month in Waterloo is January, with average low temperatures of -3°C. The average temperature during this period is around 1°C.

What is the wettest time of year in Waterloo?

The wettest month in Waterloo is April, with an average of 142mm of precipitation.

What is the driest time of year in Waterloo?

The driest month in Waterloo is November, with an average of 67mm of precipitation.

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