SeasonMapWhat's on in Boise, United States through the year
Boise, United States has 5 curated events through the year — 2 festivals, 2 hazard seasons and 1 seasonal opening. The ones to plan around: Treefort Music Fest (March) and Float the Boise season (June). March and August are its peak-crowd months.
Updated September 2026 · every event curated and sourced · dates for 2026 where they are announced, the usual window where they are not
Boise events and crowds by month
January in Boise
Boise weather in January →Busy — Winter / Christmas break in United States, school holidays in 2 of the markets that fill it
Nothing new starts in January.
Still on: Winter inversion (15 Nov – 15 Feb (usually))
February in Boise
Boise weather in February →Quiet — one of its worst months for weather
Nothing new starts in February.
Still on: Winter inversion (15 Nov – 15 Feb (usually))
March in Boise
Boise weather in March →Peak crowds — Treefort Music Fest, Spring break in United States
- Festival
Treefort Music Fest
20 Mar – 5 Apr · usuallyMajor festivalCrowdedBook earlyFive days and several hundred acts across venues you can walk between, plus the side forts — food, film, yoga, talks — that make it more than a music bill. Downtown hotels go early and the weather can be anything. Source ↗
April in Boise
Boise weather in April →Busy — Treefort Music Fest
Nothing new starts in April.
Still on: Treefort Music Fest (20 Mar – 5 Apr (usually))
May in Boise
Boise weather in May →Busy — one of its best months for weather
Nothing new starts in May.
June in Boise
Boise weather in June →Busy — Summer break in United States, school holidays in 2 of the markets that fill it
- Opening
Float the Boise season
20 Jun – 7 Sep · usuallySummer season opensThe city opens the river to tubes once the spring runoff drops to a safe flow, usually late June, and shuts it on Labor Day when the shuttle and rental stop. The start date is announced a week or two ahead, not fixed. Source ↗
July in Boise
Boise weather in July →Busy — Summer break in United States, school holidays in 2 of the markets that fill it
- Hazard
Wildfire smoke season
1 Jul – 20 Sep · usuallySmoke from fires in the Idaho backcountry and from Oregon and California settles into the valley for stretches of days at a time. Some summers barely register; in a bad one the foothills disappear for a fortnight. Source ↗
Still on: Float the Boise season (20 Jun – 7 Sep (usually))
August in Boise
Boise weather in August →Peak crowds — Western Idaho Fair, Summer break in United States
- Festival
Western Idaho Fair
14–30 Aug · usuallyMajor festivalCrowdedTen days of livestock barns, fried food and grandstand concerts at Expo Idaho, and the closest thing the Treasure Valley has to a shared calendar date. Evenings are the only tolerable time to walk it. Source ↗
Still on: Float the Boise season (20 Jun – 7 Sep (usually)), Wildfire smoke season (1 Jul – 20 Sep (usually))
September in Boise
Boise weather in September →Busy — Summer break in United States
Nothing new starts in September.
Still on: Float the Boise season (20 Jun – 7 Sep (usually)), Wildfire smoke season (1 Jul – 20 Sep (usually))
October in Boise
Boise weather in October →Shoulder season — an ordinary month
Nothing new starts in October.
November in Boise
Boise weather in November →Busy — Thanksgiving break in United States
- Hazard
Winter inversion
15 Nov – 15 Feb · usuallyWinter smogCold air pools in the U-shaped valley under a warm lid and the wood smoke and traffic exhaust stay with it, sometimes for weeks. Drive twenty minutes up into the foothills and you come out above it into sunshine. Source ↗
December in Boise
Boise weather in December →Busy — Winter / Christmas break in United States, school holidays in 2 of the markets that fill it
Nothing new starts in December.
Still on: Winter inversion (15 Nov – 15 Feb (usually))