Weatheo

Waterloo Weather by Month

Average temperatures, rainfall and humidity for Waterloo, United States, month by month, built from OpenWeather’s historical records. Use it to see what a typical Waterloo month looks like before you travel — then check the live Waterloo forecast for the days ahead.

Warmest month

July

29°C average high

Coolest month

January

-10°C average low

Wettest month

June

109 mm of rain

Driest month

February

17 mm of rain

Average temperature and rainfall in Waterloo by month

Averages of the daily highs and lows recorded in each month, with total rainfall, mean humidity and mean wind speed.

MonthAvg highAvg lowRecord low / highRainfallHumidityWind
January-1°C-10°C-32°C / 14°C
19 mm
80%16 km/h
February1°C-9°C-33°C / 24°C
17 mm
77%17 km/h
March9°C-1°C-25°C / 31°C
39 mm
73%18 km/h
April16°C5°C-10°C / 29°C
80 mm
67%20 km/h
May23°C11°C-1°C / 36°C
87 mm
68%16 km/h
June28°C17°C7°C / 39°C
109 mm
71%14 km/h
July29°C18°C9°C / 36°C
62 mm
77%11 km/h
August28°C17°C9°C / 38°C
59 mm
79%11 km/h
September26°C14°C0°C / 37°C
86 mm
74%12 km/h
October18°C7°C-6°C / 33°C
72 mm
71%15 km/h
November9°C0°C-18°C / 24°C
39 mm
76%16 km/h
December3°C-5°C-26°C / 23°C
29 mm
80%16 km/h

Best time to visit Waterloo

The most comfortable time to visit Waterloo is generally May and August to September, balancing mild daytime temperatures against the driest stretch of the year. The city has strongly marked seasons and rain concentrates around June, totalling about 698 mm a year.

Travellers who prefer heat should aim for July, when highs average 29°C. June is the month to avoid if rain would spoil your plans — it averages 109 mm, roughly 7× the rainfall of the driest month (February).

Source: OpenWeather historical and statistical weather data. Values are long-term averages, not a forecast — see the Waterloo forecast for what is happening now.

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