Bozeman is the sunniest city in Montana, averaging over 300 sunny days per year. Bozeman’s average annual precipitation is 16.23 inches and Belgrade’s is 14.8 inches. Humidity is low in both summer and winter. Due to the dry climate, summers are pleasant with warm days and cool nights. Mild winter weather in Gallatin Valley is not unusual, and more than a week of consistently frigid weather is increasingly infrequent.
Located at 45°40′40″N, the length of the day varies significantly over the course of the year. The shortest day is December 21 with 8:41 hours of daylight; the longest day is June 20 with 15:42 hours of daylight.
Due to its elevation of 4,820 ft (1,461 m), summer temperature changes from day to night can be significant with warm sunny days and cool nights. Summer temperatures can range from 70 to 90 degrees with few days exceeding 90 degrees, and lows in the mid 40s to low 50s.
Winters in Bozeman are characterized by fluctuating temperatures with increasingly mild winters in the valley. December is typically the coldest month, with average high temperatures of 33 degrees, and average low temperature of 12 degrees. Average annual mean snowfall in the valley is 73.1 inches. The ski areas of Bridger Bowl and Big Sky are located in the mountains surrounding the valley and get over 300 inches of snow annually.
For gardeners, the Bozeman Hardiness Zone is usually considered Zone 4B. The average length of the growing season is 107 days. The first killing frost usually occurs around September 12th. Bozeman gardners can extend the growing season several weeks by covering susceptible crops overnight or use low tunnels(hoop tunnels).
|Average high in °F:||35||38||47||56||65||73|
|Average low in °F:||14||17||24||30||38||44|
|Av. precipitation in inch:||0.55||0.55||1.02||1.77||2.8||2.8|
|Average snowfall in inch:||9||6||8||4||1||0|
|Average high in °F:||83||82||72||58||43||33|
|Average low in °F:||50||48||40||32||21||12|
|Av. precipitation in inch:||1.42||1.22||1.26||1.38||0.91||0.55|
|Average snowfall in inch:||0||0||0||3||8||11|
|Annual high temperature:||57.1°F|
|Annual low temperature:||30.8°F|
|Average annual precipitation – rainfall:||16.23 inch|
|Days per year with precipitation – rainfall:||–|
|Annual days of sunshine:||300|
|Av. annual snowfall:||50 inch|