Winters in Denver are quite cold, with temperatures often dropping below freezing and averaging around -1°C in January. By March, the mercury has begun to rise, reaching average highs of 12°C as spring starts to take hold. April and May bring mild temperatures, with average highs soaring to 20-22°C by June, marking the beginning of a warm summer period that can reach scorching highs of up to 41°C in July and August. Autumn brings a return to milder weather, with October averaging highs around 14°C before dropping again into winter's chill by December, which averages just above freezing at 4°C.