Winters in Thornton are cold and variable, with temperatures often dropping below freezing and averaging around 0°C in January. As the season progresses, temperatures gradually rise, but February remains quite chilly, averaging -3°C. Spring brings a welcome warming trend, with March temperatures averaging 4°C and April experiencing mild days reaching up to 28°C. Summer months are warm, with June and July often seeing highs above 40°C, while August and September remain slightly cooler. Autumn is characterized by a return to cooler temperatures, with October averaging around 11°C before dropping again in November and December.