Unlike most northwestern cities, Missoula is lucky to have four distinct seasons. Yet, when planning a trip to Missoula, the name of the game is layers. Missoula weather is much more temperate than the rest of the state, making it an ideal destination in both the summer and the winter.
With colder temperatures in the mornings and evenings, layers let you adjust without too much discomfort. Located in a valley, Missoula remains generally dry, because a large portion of the precipitation is lost as the clouds pass over the Rockies.
Spring in Missoula is nice, once it arrives. Winter tends to hang on, offering late snows, sometimes as late as May. When it isn't snowing expect the rain. May and June are some of the wettest months in Missoula, with almost daily drizzles. Expect highs to vary from 45ºF to 66ºF and lows to drop into the 30's. Don't forget those layers, because when the sun goes down, you will want that extra clothing.
This can be a wonderful time to visit if you don't mind the unpredictable weather. During March and April, you can still catch some good skiing up in the mountains, while further into May, you will experience budding tulips and the return of green grass along the mountainsides.
The summer months are when Missoula comes alive. People are excited to be outside and the rivers and lakes quickly fill up with folks looking to cool off, while the hillsides become covered with hikers. This “Garden City” is full of sunshine and moderate temperatures all summer, ranging from 73ºF to 85ºF, but spikes up into the 90's are not uncommon. Evenings are still a tad chilly, so make sure to bring a light jacket.
During the summer, Missoula can be very dry, especially in July and August. Unfortunately, this often causes horrible forest fires that leave the town blanketed in thick layers of smoke. Some years are worse then others, while others don't experience any fires, so make sure and check with the forest service.
Fall in Missoula can be great. Expect clear days and mild temperatures that get progressively colder and darker as winter nears. But, a day or two of really warm weather is not uncommon. Temperatures start in October around 50ºF and gradually drop. It's not uncommon for evening temperatures to drop into the 30's.
Even though the weather is starting to get colder, the hiking is still great this time of year. Little precipitation is common, but pack a ran coat for the unexpected shower. As the leaves start to change, a hike up the “M” trail found on Mt. Sentinel is a must. From here, Missoula's tree lined streets display the beautiful colors of fall.
The Continental Divide protects Missoula from the harsh arctic cold fronts that move in from Canada. So while other parts of the state may be experiencing near zero conditions, Missoula winter temperatures tend to hang around the 30's, while dropping into the high to low teens at night. The arctic cold does breakthrough every now and then creating severe winter blizzards, but these are generally short lived.
Missoula Valley does not get as much snow as other parts of the state, but it does manage to accumulate a couple feet over the winter months. Just what you need for some good snowshoeing or cross-country skiing.
Missoula does experience winter inversion, sometimes lasting all winter, so don't expect to see too much of the sun. If this starts to bother you, a quick trip up to one of the ski resorts will take you above the cloud line for a bit of sunshine.