In September, Joetsu typically sees daytime highs of 25.4°C and overnight lows around 16.9°C. Compared to the annual average high of 17.1°C, September runs +8.2°C.
September in Joetsu averages a daytime high of 25.4°C and an overnight low of 16.9°C.
September runs +8.2°C compared to Joetsu's annual average high of 17.1°C, ranking #3 of 12 months by warmth.
Plan for daytime highs near 25.4°C and cooler evenings around 16.9°C.