Winter in Terrebonne is harsh, with temperatures frequently dropping below -20°C, averaging around -6°C in January and -7°C in February. Spring brings gradual warming, with March temperatures ranging from -19°C to 22°C, while April's average temperature jumps to a relatively mild 8°C. Summer months are mild to warm, with July and August averages hovering around 20-22°C, punctuated by occasional heatwaves up to 33-35°C. Autumn is similarly moderate, with September averaging 17°C and October 11°C, before temperatures drop again in November and December.