Temperature
Warm by day, brisk at night.
84°Ftypical September high
Typical range
September climate
September in Boise
United States · North America
Warm days and plenty of sun.
One of the best months here
Mid to late
Daytime high
84°F
Lows around 56°F
Rain
Very little rain
Sun
11.5 h/day
Air feel
Very dry
When to visit
Month-by-month fit
Best
Precipitation
Mostly dry. About 2 wet days, fewer than in most months.
7%wet-day frequency
Precip amountWet-day chanceSnowfall
Sunshine
Plenty of sun this month.
11.5 hSeptember sunshine
Heat & humidity by month
Warm days with mostly dry air.
Very drySeptember Heat feel
Easy airWarm airHot airHumid air
Hourly temperature pattern
In September, afternoons feel about 72° and nights feel near 52°.
FreezingVery coldColdCoolComfortableWarmHotNight hours
Clear sky
Mostly clear skies this month.
72%September Clear sky
Clear skyCloud
Wind pattern
Calm winds are typical in September.
6 mphSeptember Calm
More detailIncludes daypart comfort
Typical September day
September late afternoons are around 80°F, easing to about 77°F in early evening.
Avg temp Typical range
Morning65°F
Rain3%
Cloud27%
Humid airLow
Sun intensityLow
Midday74°F
Rain3%
Cloud27%
Humid airLow
Sun intensityStrong
Late afternoon80°F
Rain3%
Cloud31%
Humid airLow
Sun intensityStrong
Early evening77°F
Rain2%
Cloud30%
Humid airLow
Sun intensityLow
Best windowData tableView month-by-month numbers
View month-by-month numbers
| Month | High°F | Low°F | Rainin | Wet days | Sunh | Humidity% |
|---|---|---|---|---|---|---|
| Jan | 42 | 29 | 1.8 | 10 | 6.8 | 73 |
| Feb | 47 | 32 | 1.3 | 8 | 8.1 | 67 |
| Mar | 58 | 38 | 1.5 | 9 | 9.6 | 58 |
| Apr | 66 | 42 | 1.1 | 7 | 11.2 | 48 |
| May | 75 | 50 | 1.2 | 6 | 12.7 | 45 |
| Jun | 85 | 57 | 0.5 | 3 | 13.7 | 39 |
| Jul | 96 | 65 | 0.1 | 1 | 14.1 | 29 |
| Aug | 94 | 64 | 0.2 | 1 | 13.2 | 30 |
| Sep | 84 | 56 | 0.4 | 2 | 11.5 | 37 |
| Oct | 68 | 45 | 0.9 | 5 | 9.6 | 50 |
| Nov | 52 | 36 | 1.3 | 7 | 7.3 | 64 |
| Dec | 42 | 30 | 2.1 | 10 | 6.3 | 72 |
Similar climates
Similar
Similar travel styleDenverUnited StatesSimilar travel styleMoabUnited StatesSimilar travel styleLake TahoeUnited StatesSimilar travel styleJackson HoleUnited States
Want a side-by-side climate view? Compare Boise with Denver.
Climate data notePlanning guidance, not a forecast
Typical monthly values are based on long-term climate records. Useful for planning, not a forecast. Check the weather before you travel.
Sunshine: source type is not yet identified at metric level.
Local microclimates can vary by beach, neighborhood, trail, or elevation.
Last updated: Jun 1, 2026
Data & methodology