If you're looking for summer vibes, the best time to travel to Waterloo is in January, February and December, when the average temperature reaches 29.78 °C, while July, August and September are the 3 sunniest months of the year, with an average of 100.94 hours.
If you prefer colder temperatures, however, make sure you visit Waterloo during the months of July, August and June to experience an average of 9.63 °C.
For those who don't care too much about temperatures, but want to avoid getting wet in the rain, it's important to avoid travelling during January, May and June, when the average precipitation in Waterloo is 7.5 mm, while the months of January, February and March are drier, with an average of 0 mm.