Windsor's winters are cold, with temperatures often below freezing and averaging around -1°C in January, but gradually warming up by February. Spring arrives slowly, with temperatures fluctuating wildly in March before stabilizing by April, when the average high reaches 10°C. Summer is warm to hot, with July and August temperatures rarely dipping below 13°C, and highs often reaching into the mid-30s. Autumn brings a return to cooler temperatures, with September experiencing a brief respite from summer's heat, but October and November are similar to winter in their chilliness. Winter returns by December, with temperatures averaging just above freezing.