Boise weather by month

Check out Boise weather averages by month. Compare detailed monthly climate statistics including temperature, rainfall and sunshine figures.

Temperature in Boise (°C)

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Max temperature (daytime)
2°C maximum daytime temperature in January in Boise2
7°C maximum daytime temperature in February in Boise7
12°C maximum daytime temperature in March in Boise12
16°C maximum daytime temperature in April in Boise16
22°C maximum daytime temperature in May in Boise22
27°C maximum daytime temperature in June in Boise27
32°C maximum daytime temperature in July in Boise32
31°C maximum daytime temperature in August in Boise31
25°C maximum daytime temperature in September in Boise25
18°C maximum daytime temperature in October in Boise18
9°C maximum daytime temperature in November in Boise9
3°C maximum daytime temperature in December in Boise3
Min temperature (night-time)
-6°C minimum night-time temperature in January in Boise-6
-3°C minimum night-time temperature in February in Boise-3
-1°C minimum night-time temperature in March in Boise-1
2°C minimum night-time temperature in April in Boise2
6°C minimum night-time temperature in May in Boise6
11°C minimum night-time temperature in June in Boise11
14°C minimum night-time temperature in July in Boise14
13°C minimum night-time temperature in August in Boise13
8°C minimum night-time temperature in September in Boise8
3°C minimum night-time temperature in October in Boise3
-1°C minimum night-time temperature in November in Boise-1
-6°C minimum night-time temperature in December in Boise-6
Heat & Humidity
No heat & humidity in January in Boise0
No heat & humidity in February in Boise0
No heat & humidity in March in Boise0
No heat & humidity in April in Boise0
No heat & humidity in May in Boise0
Low heat & humidity in June in BoiseL
Moderate heat & humidity in July in BoiseM
Moderate heat & humidity in August in BoiseM
No heat & humidity in September in Boise0
No heat & humidity in October in Boise0
No heat & humidity in November in Boise0
No heat & humidity in December in Boise0

Note: 0 = None, L = Low, M = Moderate, H = High, VH = Very high, E = Extreme

Sunshine & Daylight in Boise

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Daily hours of sunshine
Daily hours of daylight
9 hours of daylight per day in January in Boise9
11 hours of daylight per day in February in Boise11
12 hours of daylight per day in March in Boise12
13 hours of daylight per day in April in Boise13
15 hours of daylight per day in May in Boise15
15 hours of daylight per day in June in Boise15
15 hours of daylight per day in July in Boise15
14 hours of daylight per day in August in Boise14
12 hours of daylight per day in September in Boise12
11 hours of daylight per day in October in Boise11
10 hours of daylight per day in November in Boise10
9 hours of daylight per day in December in Boise9
UV Index (Maximum)
UV (maximum) index 1 (Low) in January in Boise1
UV (maximum) index 2 (Low) in February in Boise2
UV (maximum) index 4 (Moderate) in March in Boise4
UV (maximum) index 6 (High) in April in Boise6
UV (maximum) index 7 (High) in May in Boise7
UV (maximum) index 9 (Very High) in June in Boise9
UV (maximum) index 9 (Very High) in July in Boise9
UV (maximum) index 8 (Very High) in August in Boise8
UV (maximum) index 6 (High) in September in Boise6
UV (maximum) index 4 (Moderate) in October in Boise4
UV (maximum) index 2 (Low) in November in Boise2
UV (maximum) index 1 (Low) in December in Boise1

Rainfall in Boise

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Number of days with some rain
12 days with some rainfall in January in Boise12
10 days with some rainfall in February in Boise10
10 days with some rainfall in March in Boise10
8 days with some rainfall in April in Boise8
7 days with some rainfall in May in Boise7
6 days with some rainfall in June in Boise6
3 days with some rainfall in July in Boise3
3 days with some rainfall in August in Boise3
4 days with some rainfall in September in Boise4
6 days with some rainfall in October in Boise6
10 days with some rainfall in November in Boise10
11 days with some rainfall in December in Boise11
Average monthly rainfall (mm)
38 mm monthly rainfall in January in Boise38
28 mm monthly rainfall in February in Boise28
32 mm monthly rainfall in March in Boise32
30 mm monthly rainfall in April in Boise30
27 mm monthly rainfall in May in Boise27
21 mm monthly rainfall in June in Boise21
8 mm monthly rainfall in July in Boise8
10 mm monthly rainfall in August in Boise10
19 mm monthly rainfall in September in Boise19
19 mm monthly rainfall in October in Boise19
38 mm monthly rainfall in November in Boise38
36 mm monthly rainfall in December in Boise36

More about Boise

Boise by month

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The climate guide for Idaho (Boise) shows long term monthly weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

What's the climate like in Boise?

Boise has a cool semi arid climate with hot summers.

Metric (°C / mm)  |  Imperial (°F / inches)

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More about the USA

Compare Boise with the USA

Below the Boise chart shows average maximum daytime temperature for Boise, Idaho, USA and the USA (Washington).

Maximum daytime temperature (°C)

Boise, Idaho, USA
USA (Washington)
2
5
7
7
12
13
16
19
22
24
27
29
32
31
31
30
25
26
18
20
9
14
3
8
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Metric (°C / mm)  |  Imperial (°F / inches)

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