Temperature for December 1999
In December 1999 the average high temperature in Great Falls, MT was 47.4°F, and this was 10.7°F warmer than the average of 36.7°F. The hottest day in December 1999 was 29 December when the temperature reached 57.9°F. Overnight the average temperature in December is 16.8°F and in 1999 the average overnight temperature was 8.0°F warmer at 24.7°F.