S
M
T
W
T
F
S
26
87°
69°
27
89°
70°
28
88°
69°
29
89°
70°
30
90°
69°
31
87°
69°
1
82°
67°
2
82°
64°
3
83°
66°
4
82°
68°
5
81°
68°
6
82°
67°
7
82°
66°
8
83°
66°
9
84°
68°
10
85°
68°
11
85°
67°
12
86°
67°
13
87°
66°
14
91°
66°
15
91°
67°
16
89°
67°
17
83°
66°
18
86°
67°
19
84°
62°
20
84°
59°
21
82°
58°
22
81°
58°
23
82°
60°
24
82°
59°
25
83°
60°
26
83°
65°
27
86°
63°
28
87°
62°
29
84°
61°
30
86°
59°
31
82°
58°
1
80°
61°
2
82°
64°
3
81°
59°
4
81°
57°
5
83°
60°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Foster
Foster's August 2026 forecast shows daily high temperatures ranging from 80° to 91°, with overnight lows between 57° and 70°. The average high for August is 84° with an average low of 64°. 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 Foster. See also: September | October | November.
