Glacier Park’s climate is wet and windy. As one of the wettest locations in Montana, the park receives an average of 42 inches of annual precipitation, with western park areas gleaning the most moisture, growing drier as you move in an easterly direction. This phenomenon is in part due to frequent Chinook winds, blowing from the south and southwest. Regardless of the time of year, when visiting Glacier, always be prepared for moist and gusty conditions. Pack layers and check weather conditions before heading out.
Glacier summers tend to be short and cool. June is one of the wettest months so bring your rain gear; July and August are the warmest and sunniest times to visit. Average summer temperatures range between 60º – 70º F, with the occasional hot day reaching upwards of 90º F.
Fall can be a very rewarding time to visit the park, with fewer crowds, easily spotted wildlife due to rutting season, and aspens and other foliage in vibrant color. September and October are considered autumnal months, with cooler, ranging temperatures and higher gusts (upwards of 60 miles per hour) than in summer.
Glacier winters are long, however generally mild due to warm Chinook winds carrying Pacific air up and over the Rockies. November kicks off winter and with it comes an abundance of precipitation, mainly snowfall. Average snow accumulations can reach 225 inches with much more at higher elevations. January and February are the coldest months, when temperatures can dip down to -40ºF however milder temperatures are much more common, sometimes climbing to 50ºF.
Warm spring weather brings run-off season to Glacier. April is characterized as one of the wettest months, however the warmer temperatures (averaging 40ºF) combined with the moisture stimulates the growth of lush flora and fauna.