Winters in Richmond Hill are typically cold and snowy, with temperatures often dropping below -20°C in January and February, but gradually warming up by March. Spring arrives in April, bringing mild temperatures that can rise above 20°C, but still experiencing chilly mornings. Summer is warm and humid, with July and August being the hottest months, while September brings a gentle cool-down before autumn sets in. Autumn is generally mild, with temperatures ranging from 0 to 25°C, but can be unpredictable. By December, the cold winter air returns, bringing temperatures back down around freezing point.