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 (°F)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Max temperature (daytime)	36	45	54	61	72	81	90	88	77	64	48	37
Min temperature (night-time)	21	27	30	36	43	52	57	55	46	37	30	21
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 (inches)	1.5	1.1	1.3	1.2	1.1	0.8	0.3	0.4	0.7	0.7	1.5	1.4

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 36°F 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.

36
36°F max day temperature
4
4 hours of sunshine per day
12
12 days with some rainfall
21
21°F min night temperature
9
9 hours of daylight per day
0
No heat & humidity
1.5
1.5 inches of monthly rainfall
1
1 (Low) UV index

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Boise weather in February

Expect daytime maximum temperatures of 45°F 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.

45
45°F max day temperature
5
5 hours of sunshine per day
10
10 days with some rainfall
27
27°F min night temperature
11
11 hours of daylight per day
0
No heat & humidity
1.1
1.1 inches of monthly rainfall
2
2 (Low) UV index

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Boise weather in March

Expect daytime maximum temperatures of 54°F 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.

54
54°F max day temperature
8
8 hours of sunshine per day
10
10 days with some rainfall
30
30°F min night temperature
12
12 hours of daylight per day
0
No heat & humidity
1.3
1.3 inches of monthly rainfall
4
4 (Moderate) UV index

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Boise weather in April

Expect daytime maximum temperatures of 61°F in Boise, Idaho in April based on long-term weather averages. There are 9 hours of sunshine per day on average.

61
61°F max day temperature
9
9 hours of sunshine per day
8
8 days with some rainfall
36
36°F min night temperature
13
13 hours of daylight per day
0
No heat & humidity
1.2
1.2 inches of monthly rainfall
6
6 (High) UV index

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Boise weather in May

Expect daytime maximum temperatures of 72°F in Boise, Idaho in May based on long-term weather averages. There are 11 hours of sunshine per day on average.

72
72°F max day temperature
11
11 hours of sunshine per day
7
7 days with some rainfall
43
43°F min night temperature
15
15 hours of daylight per day
0
No heat & humidity
1.1
1.1 inches of monthly rainfall
7
7 (High) UV index

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Boise weather in June

Expect daytime maximum temperatures of 81°F in Boise, Idaho in June based on long-term weather averages. There are 12 hours of sunshine per day on average.

81
81°F max day temperature
12
12 hours of sunshine per day
6
6 days with some rainfall
52
52°F min night temperature
15
15 hours of daylight per day
L
Low heat & humidity
0.8
0.8 inches of monthly rainfall
9
9 (Very High) UV index

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Boise weather in July

Expect daytime maximum temperatures of 90°F in Boise, Idaho in July based on long-term weather averages. There are 13 hours of sunshine per day on average.

90
90°F max day temperature
13
13 hours of sunshine per day
3
3 days with some rainfall
57
57°F min night temperature
15
15 hours of daylight per day
M
Moderate heat & humidity
0.3
0.3 inches of monthly rainfall
9
9 (Very High) UV index

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Boise weather in August

Expect daytime maximum temperatures of 88°F in Boise, Idaho in August based on long-term weather averages. There are 12 hours of sunshine per day on average.

88
88°F max day temperature
12
12 hours of sunshine per day
3
3 days with some rainfall
55
55°F min night temperature
14
14 hours of daylight per day
M
Moderate heat & humidity
0.4
0.4 inches of monthly rainfall
8
8 (Very High) UV index

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Boise weather in September

Expect daytime maximum temperatures of 77°F in Boise, Idaho in September based on long-term weather averages. There are 10 hours of sunshine per day on average.

77
77°F max day temperature
10
10 hours of sunshine per day
4
4 days with some rainfall
46
46°F min night temperature
12
12 hours of daylight per day
0
No heat & humidity
0.7
0.7 inches of monthly rainfall
6
6 (High) UV index

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Boise weather in October

Expect daytime maximum temperatures of 64°F in Boise, Idaho in October based on long-term weather averages. There are 8 hours of sunshine per day on average.

64
64°F max day temperature
8
8 hours of sunshine per day
6
6 days with some rainfall
37
37°F min night temperature
11
11 hours of daylight per day
0
No heat & humidity
0.7
0.7 inches of monthly rainfall
4
4 (Moderate) UV index

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Boise weather in November

Expect daytime maximum temperatures of 48°F 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.

48
48°F max day temperature
4
4 hours of sunshine per day
10
10 days with some rainfall
30
30°F min night temperature
10
10 hours of daylight per day
0
No heat & humidity
1.5
1.5 inches of monthly rainfall
2
2 (Low) UV index

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Boise weather in December

Expect daytime maximum temperatures of 37°F 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.