Montana Weather / Climate

No matter what time of year it is in Montana there is always the potential for extreme weather conditions-the state's weather can change drastically in a matter of minutes.

Spring
Spring is a time of cold to mild temperatures. Temperatures in Helena, the State’s capital range from 30 degrees F to 50 degrees F from March through June.

During the early spring, warm, dry winter winds coming off the east slopes of the Rockies and across the plains affect the weather. These Chinooks are created as the Pacific air passes over the mountains, dumping its moisture and being warmed on its eastern down slope run.

May and June are the wettest months over a majority of the state, with the northwest receiving most of its precipitation from winter Pacific storms.

Summer
Summers in the eastern portion of the State can get very hot. Record highs have been recorded at Glendive and Medicine Lake – both at 117 degrees F.

The first part of July and into August, temperatures in Helena fluctuate from a low of 50 degrees F to a high of 85 degrees F.

Historically, the warmest months are July and August, where, although scarce, rain can dampen even the finest picnic. During these months, brief mid-day thunderstorms are a common sight with heavy downpours cooling the late afternoon temperatures

Fall
By the time September rolls around, the weather takes a slight change with cooler and wetter conditions prevailing. But, in October when fall colors are usually thriving across the state, there is the frequent potential of an Indian summer, which brings lovely mild temperatures and big blue skies.

Winter
Tales of extreme weather conditions abound in Montana. Indeed, it can get cold; the lowest temperature in the lower 48 states was recorded at Rogers Pass, northwest of Helena, in 1954 - a numbing negative 70 degrees.

Old Man winter can shake his beard at any time bringing wintry weather, but it usually doesn't get severe until the end of November with roads staying clear until that point.

Winter cold is the greatest weather concern. Roads can be downright awful if snow-covered, and incremental melting leaves small, invisible patches of black ice on the road.

If you travel by car in Montana in the winter, make sure you have tire chains, and know how to put them on. Pay attention to road and weather reports, and don't take chances. This shouldn't deter you from visiting one of the last great open frontiers in the country, just a precaution that while in Montana be responsible.