Climate almanac
Waterloo
Illinois, United States · 38.34°, -90.15°
What is the weather like in Waterloo in May?
In May, Waterloo is typically 77°F (25°C) during the day and 59°F (15°C) at night. The month brings about 5.5 in (140 mm) of precipitation in total.
- Average high77°F (25°C)
- Average low59°F (15°C)
- Precipitation5.5 in (140 mm)
- Clear or mostly clear days8
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)