Winters in Mentor are cold, with temperatures often below freezing, and occasional drops as low as -18C. Temperatures slowly warm up in spring, but still experience chilly nights, while days can rise into the mid-20s by April. Summers are mild to warm, with highs consistently above 30C, but rarely reaching extreme heat. Autumn brings a return to cooler temperatures, with some warmer days lingering into October before dropping back down into the chill of winter. Overnight lows in all seasons remain relatively cool, often ranging from just below freezing to around 10-15C.