In September, Bialystok typically sees daytime highs of 18.6°C and overnight lows around 6.5°C. Compared to the annual average high of 11.8°C, September runs +6.8°C.
September in Bialystok averages a daytime high of 18.6°C and an overnight low of 6.5°C.
September runs +6.8°C compared to Bialystok's annual average high of 11.8°C, ranking #5 of 12 months by warmth.
Plan for daytime highs near 18.6°C and cooler evenings around 6.5°C.