In September, Shiojiri typically sees daytime highs of 22.9°C and overnight lows around 14.0°C. Compared to the annual average high of 14.4°C, September runs +8.5°C.
September in Shiojiri averages a daytime high of 22.9°C and an overnight low of 14.0°C.
September runs +8.5°C compared to Shiojiri's annual average high of 14.4°C, ranking #3 of 12 months by warmth.
Plan for daytime highs near 22.9°C and cooler evenings around 14.0°C.