Typical Weather in Great Falls, MT in May
67° F Avg High
42° F Avg Low
6 Rainy Days
☀️ Temperature Summary
Highs in May are typically around 67°F, which is warmer than usual in Great Falls. Lows overnight are typically around 42°F. Temperatures will generally increase as the month goes on, with daily high temperatures ranging between 63°F and 72°F.
May is a great time to visit Great Falls, with mild temperatures and sunny days being very common.
High Temps Throughout the Year
☔ Rain Summary
You can expect about a 20% chance of rain for any given day in May. It's one of the rainier months of the year for Great Falls, with total rainfall for the month around 3 inches.
Rainfall Throughout the Year
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