Some snow flurries are common in early spring in Montana. It can be quite wet, as the mountain peaks receive a snow and rain mix while the lowland receives most of its rain in May and June. The eastern half of Montana tends to warm up sooner than western Montana in the spring.
July through September are Montana's summer months. For the most part, daily high temperatures hold steady between 70 and 90 degrees, but occasional heat waves do soar through the state. This is an ideal time to make it up to higher elevations since they are cooler. Summer thunderstorms occur in eastern Montana, while the national park areas in the west have dry thunderstorms with lightning that can potentially start wild fires.
The weather in Montana becomes increasingly cloudy starting in mid-October. There can be some snow flurries, but mostly wet rain sets in. Cold front winds from Canada sweep into eastern Montana, causing it to become colder than the western half.
Winter snowfall is common across the entire state, but the western mountains of Montana receive the most, usually around 250 inches. Blowing snow, or blizzards, are more common in the east. The amount of snow per region depends on altitude; many valleys will not see much more than 50 inches each year.
