nomadseason

May Weather in Waterloo, United States

Last updated: June 24, 2025

In May, the average temperature in Waterloo, United States is a pleasant 20°C (68°F), ranging from a chilly 4°C (39°F) to a warm 34°C (93°F). Expect 149 mm (5.9 in) of precipitation over 14 days, complemented by an average humidity level of 82%. Whether you're exploring the outdoors or enjoying cozy indoor activities, this month offers a variety of experiences!

May Temperature in Waterloo

In May in Waterloo, the average temperature is 20°C (68°F). The maximum can reach 34°C (93°F), while the minimum can be as low as 4°C (39°F). Overall, this month offers a pleasant variety of temperatures, making it an excellent time for travelers to explore the region.

May Weather in Waterloo: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Waterloo, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Waterloo, May typically has an average temperature of 20°C (68°F), with highs reaching up to 34°C (93°F) and lows dropping to around 4°C (39°F).
JanFebMarAprMayJunJulAugSepOctNovDec343748566777807772594540
Data source: Temperature data for Waterloo generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in Waterloo

In Waterloo in May, the precipitation amount is 149 mm (5.9 in) over a span of 14 days.

May Precipitation Trends in Waterloo

The chart displays monthly precipitation patterns in Waterloo, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In Waterloo, May typically receives around 149 mm (5.9 inches) of precipitation spread over approximately 14 days.
JanFebMarAprMayJunJulAugSepOctNovDec79871361421498789123661097568
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

May Humidity in Waterloo

In Waterloo in May humidity is 82%. With an average temperature of 20°C (68°F), this humidity feels like a warm, enveloping blanket that makes traveling a bit sluggish but surprisingly refreshing, as long as you take breaks in shaded areas to cool off.

May Average Humidity in Waterloo

This chart illustrates the average monthly humidity levels in Waterloo, with May’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In May, average humidity in Waterloo is approximately 82%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec82%80%80%80%82%83%81%80%76%76%85%86%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Waterloo

In Waterloo in May, the maximum UV index reaches 10, which corresponds to a very high Exposure Category. With a time to burn of just 15 minutes, it's crucial to take precautions. For more detailed information, you can check the Hourly UV Index in Waterloo.

Maximum UV Index Levels in Waterloo for May

The chart shows the monthly maximum UV Index (UVI) for Waterloo in May, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In May, the maximum UV index in Waterloo typically reaches 10, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec3579101110109753
Data source: Waterloo May UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

How May Weather in Waterloo Compares to Other Months

Weather in Waterloo varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Waterloo, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Waterloo, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather1°C (34°F)79 mm (3.1 inches)82%moderate
February Weather3°C (37°F)87 mm (3.4 inches)80%moderate
March Weather9°C (48°F)136 mm (5.4 inches)80%high
April Weather13°C (56°F)142 mm (5.6 inches)80%very high
May Weather20°C (68°F)149 mm (5.9 inches)82%very high
June Weather25°C (77°F)87 mm (3.4 inches)83%extreme
July Weather27°C (80°F)89 mm (3.5 inches)81%very high
August Weather25°C (77°F)123 mm (4.8 inches)80%very high
September Weather22°C (73°F)66 mm (2.6 inches)76%very high
October Weather15°C (60°F)109 mm (4.3 inches)76%high
November Weather7°C (45°F)75 mm (2.9 inches)85%moderate
December Weather4°C (40°F)68 mm (2.7 inches)86%moderate

Compare Waterloo's Climate with Cities Worldwide