Fall Weather and Temperatures in Japan Autumn in Japan comprises the months of September, October, and November. In September, temperatures tend to be around 23ºC to 28ºC (73°F to 82°F) in the afternoon and drop to about 18ºC to 21ºC (64°F to 70°F) in the morning and at night.

Weather in Japan during September and October is a study in transition. September is often considered an extension of summer, particularly in the first half of the month, with high humidity and temperatures lingering around 25°C to 30°C in cities like Tokyo and Kyoto. Crucially, September is the peak of the typhoon season, which can bring heavy rain and travel disruptions. By October, the weather becomes significantly more pleasant and is arguably the best time to visit. The humidity drops, and clear, "crisp" blue-sky days become the norm with average temperatures of 15°C to 22°C. This period also marks the beginning of the autumn foliage (Koyo) season; while the vibrant red maples typically hit central Japan in November, the higher elevations of Hokkaido and the Japanese Alps begin their transformation in late September and October, offering breathtaking scenery for hikers and photographers under cool, stable weather conditions.