S
M
T
W
T
F
S
26
94°
64°
27
90°
65°
28
89°
63°
29
85°
64°
30
88°
60°
31
92°
59°
1
94°
63°
2
90°
64°
3
89°
62°
4
85°
59°
5
85°
58°
6
91°
62°
7
93°
64°
8
94°
65°
9
93°
67°
10
91°
67°
11
87°
66°
12
85°
64°
13
83°
62°
14
82°
61°
15
83°
59°
16
86°
59°
17
89°
60°
18
91°
64°
19
93°
64°
20
90°
64°
21
98°
66°
22
96°
66°
23
99°
67°
24
97°
65°
25
96°
70°
26
103°
71°
27
96°
78°
28
98°
72°
29
92°
71°
30
89°
66°
31
N/A
1
83°
54°
2
84°
56°
3
84°
57°
4
83°
59°
5
85°
62°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
August Weather in Simi Valley
Simi Valley's August 2026 forecast shows daily high temperatures ranging from 83° to 85°, with overnight lows between 54° and 62°. The average high for August is 84° with an average low of 58°. 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 Simi Valley. See also: September | October | November.
