Boise weather by month

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

Temperature
Rainfall
Sunshine & UV index

Temperature in Boise (°C)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Max temperature (daytime)	2	7	12	16	22	27	32	31	25	18	9	3
Min temperature (night-time)	-6	-3	-1	2	6	11	14	13	8	3	-1	-6
Heat & Humidity	0	0	0	0	0	L	M	M	0	0	0	0

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

Sunshine & UV index in Boise

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Daily hours of sunshine	4	5	8	9	11	12	13	12	10	8	4	3
Daily hours of daylight	9	11	12	13	15	15	15	14	12	11	10	9
UV Index (Maximum)	1	2	4	6	7	9	9	8	6	4	2	1

Rainfall in Boise

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Number of days with some rain	12	10	10	8	7	6	3	3	4	6	10	11
Average monthly rainfall (mm)	38	28	32	30	27	21	8	10	19	19	38	36

More about Boise

Boise by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

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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.

Boise weather in January

Expect daytime maximum temperatures of 2°C in Boise, Idaho in January based on long-term weather averages. There are 4 hours of sunshine per day on average with 12 days with some rainfall, which might fall as snow.

2
2°C max day temperature
4
4 hours of sunshine per day
12
12 days with some rainfall
-6
-6°C min night temperature
9
9 hours of daylight per day
0
No heat & humidity
38
38 mm of monthly rainfall
1
1 (Low) UV index

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Boise weather in February

Expect daytime maximum temperatures of 7°C in Boise, Idaho in February based on long-term weather averages. There are 5 hours of sunshine per day on average with 10 days with some rainfall.

7
7°C max day temperature
5
5 hours of sunshine per day
10
10 days with some rainfall
-3
-3°C min night temperature
11
11 hours of daylight per day
0
No heat & humidity
28
28 mm of monthly rainfall
2
2 (Low) UV index

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Boise weather in March

Expect daytime maximum temperatures of 12°C in Boise, Idaho in March based on long-term weather averages. There are 8 hours of sunshine per day on average with 10 days with some rainfall.

12
12°C max day temperature
8
8 hours of sunshine per day
10
10 days with some rainfall
-1
-1°C min night temperature
12
12 hours of daylight per day
0
No heat & humidity
32
32 mm of monthly rainfall
4
4 (Moderate) UV index

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Boise weather in April

Expect daytime maximum temperatures of 16°C in Boise, Idaho in April based on long-term weather averages. There are 9 hours of sunshine per day on average.

16
16°C max day temperature
9
9 hours of sunshine per day
8
8 days with some rainfall
2
2°C min night temperature
13
13 hours of daylight per day
0
No heat & humidity
30
30 mm of monthly rainfall
6
6 (High) UV index

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Boise weather in May

Expect daytime maximum temperatures of 22°C in Boise, Idaho in May based on long-term weather averages. There are 11 hours of sunshine per day on average.

22
22°C max day temperature
11
11 hours of sunshine per day
7
7 days with some rainfall
6
6°C min night temperature
15
15 hours of daylight per day
0
No heat & humidity
27
27 mm of monthly rainfall
7
7 (High) UV index

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Boise weather in June

Expect daytime maximum temperatures of 27°C in Boise, Idaho in June based on long-term weather averages. There are 12 hours of sunshine per day on average.

27
27°C max day temperature
12
12 hours of sunshine per day
6
6 days with some rainfall
11
11°C min night temperature
15
15 hours of daylight per day
L
Low heat & humidity
21
21 mm of monthly rainfall
9
9 (Very High) UV index

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Boise weather in July

Expect daytime maximum temperatures of 32°C in Boise, Idaho in July based on long-term weather averages. There are 13 hours of sunshine per day on average.

32
32°C max day temperature
13
13 hours of sunshine per day
3
3 days with some rainfall
14
14°C min night temperature
15
15 hours of daylight per day
M
Moderate heat & humidity
8
8 mm of monthly rainfall
9
9 (Very High) UV index

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Boise weather in August

Expect daytime maximum temperatures of 31°C in Boise, Idaho in August based on long-term weather averages. There are 12 hours of sunshine per day on average.

31
31°C max day temperature
12
12 hours of sunshine per day
3
3 days with some rainfall
13
13°C min night temperature
14
14 hours of daylight per day
M
Moderate heat & humidity
10
10 mm of monthly rainfall
8
8 (Very High) UV index

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Boise weather in September

Expect daytime maximum temperatures of 25°C in Boise, Idaho in September based on long-term weather averages. There are 10 hours of sunshine per day on average.

25
25°C max day temperature
10
10 hours of sunshine per day
4
4 days with some rainfall
8
8°C min night temperature
12
12 hours of daylight per day
0
No heat & humidity
19
19 mm of monthly rainfall
6
6 (High) UV index

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Boise weather in October

Expect daytime maximum temperatures of 18°C in Boise, Idaho in October based on long-term weather averages. There are 8 hours of sunshine per day on average.

18
18°C max day temperature
8
8 hours of sunshine per day
6
6 days with some rainfall
3
3°C min night temperature
11
11 hours of daylight per day
0
No heat & humidity
19
19 mm of monthly rainfall
4
4 (Moderate) UV index

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Boise weather in November

Expect daytime maximum temperatures of 9°C in Boise, Idaho in November based on long-term weather averages. There are 4 hours of sunshine per day on average with 10 days with some rainfall.

9
9°C max day temperature
4
4 hours of sunshine per day
10
10 days with some rainfall
-1
-1°C min night temperature
10
10 hours of daylight per day
0
No heat & humidity
38
38 mm of monthly rainfall
2
2 (Low) UV index

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Boise weather in December

Expect daytime maximum temperatures of 3°C in Boise, Idaho in December based on long-term weather averages. There are 3 hours of sunshine per day on average with 11 days with some rainfall, which might fall as snow.