In December, Olsztyn typically sees daytime highs of 0.6°C and overnight lows around -4.5°C. Compared to the annual average high of 11.0°C, December runs -10.4°C.
December in Olsztyn averages a daytime high of 0.6°C and an overnight low of -4.5°C.
December runs -10.4°C compared to Olsztyn's annual average high of 11.0°C, ranking #10 of 12 months by warmth.
Plan for daytime highs near 0.6°C and cooler evenings around -4.5°C.