...and more
In terms of precipitation, rainfall in Great Falls ranges from 0.5 - 2.5 inches per month. June is typically the wettest month, when rainfall can reach 2.5 in. January is typically the driest time to visit Great Falls when rainfall is around 0.5 in.
If weather is an important factor for your trip to Great Falls, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 68.0 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 24.8 F).