S
M
T
W
T
F
S
26
89°
65°
27
88°
68°
28
89°
66°
29
86°
66°
30
87°
65°
31
89°
67°
1
94°
67°
2
90°
67°
3
N/A
4
83°
69°
5
82°
67°
6
81°
70°
7
84°
68°
8
90°
66°
9
91°
65°
10
89°
63°
11
88°
64°
12
86°
65°
13
87°
63°
14
86°
64°
15
87°
61°
16
89°
63°
17
88°
61°
18
86°
63°
19
88°
64°
20
89°
63°
21
89°
63°
22
90°
64°
23
90°
65°
24
91°
65°
25
91°
64°
26
90°
65°
27
90°
65°
28
89°
64°
29
89°
64°
30
90°
65°
31
90°
65°
1
89°
64°
2
90°
64°
3
88°
63°
4
87°
65°
5
86°
64°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
August Weather in Mission Viejo
Mission Viejo's August 2026 forecast shows daily high temperatures ranging from 81° to 91°, with overnight lows between 61° and 70°. The average high for August is 88° 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 Mission Viejo. See also: September | October | November.
