S
M
T
W
T
F
S
26
77°
57°
27
82°
59°
28
79°
57°
29
79°
54°
30
81°
50°
31
86°
52°
1
73°
52°
2
71°
47°
3
79°
52°
4
88°
55°
5
91°
51°
6
87°
53°
7
85°
54°
8
84°
55°
9
83°
53°
10
81°
51°
11
81°
51°
12
79°
53°
13
80°
53°
14
77°
52°
15
80°
52°
16
74°
50°
17
79°
53°
18
78°
52°
19
79°
51°
20
77°
51°
21
74°
52°
22
72°
49°
23
77°
54°
24
71°
47°
25
77°
51°
26
79°
54°
27
79°
54°
28
78°
54°
29
74°
51°
30
70°
46°
31
73°
50°
1
69°
51°
2
69°
45°
3
70°
45°
4
73°
49°
5
69°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Boise
Boise's August 2026 forecast shows daily high temperatures ranging from 69° to 91°, with overnight lows between 45° and 55°. The average high for August is 77° with an average low of 51°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how August weather will actually feel in Boise. See also: September | October | November.
