In December, Great Falls typically sees daytime highs of 2.1°C and overnight lows around -9.1°C. Compared to the annual average high of 13.8°C, December runs -11.7°C.
December in Great Falls averages a daytime high of 2.1°C and an overnight low of -9.1°C.
December runs -11.7°C compared to Great Falls's annual average high of 13.8°C, ranking #11 of 12 months by warmth.
Plan for daytime highs near 2.1°C and cooler evenings around -9.1°C.