Halton Hills experiences a moderate climate with distinct seasonal patterns. Winters are typically cold, with temperatures often below freezing and occasional drops as low as -21°C in January and February. Spring arrives slowly, with temperatures gradually warming up by April, when average highs reach around 7°C. Summer is warm and pleasant, with July and August being the warmest months, averaging around 19-21°C. Autumn brings a return to cooler temperatures, with November and December experiencing occasional cold snaps and averaging around 0-3°C.