S
M
T
W
T
F
S
26
84°
68°
27
81°
67°
28
81°
63°
29
82°
68°
30
85°
68°
31
87°
67°
1
84°
66°
2
86°
67°
3
85°
59°
4
80°
62°
5
81°
63°
6
82°
61°
7
81°
60°
8
82°
59°
9
82°
62°
10
83°
65°
11
85°
59°
12
81°
59°
13
81°
58°
14
80°
58°
15
80°
62°
16
81°
60°
17
79°
58°
18
79°
56°
19
80°
56°
20
79°
61°
21
80°
64°
22
84°
66°
23
86°
66°
24
86°
64°
25
87°
59°
26
83°
58°
27
79°
58°
28
80°
62°
29
83°
54°
30
79°
54°
31
78°
55°
1
77°
58°
2
77°
59°
3
78°
55°
4
77°
52°
5
76°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Riverside
Riverside's August 2026 forecast shows daily high temperatures ranging from 76° to 87°, with overnight lows between 52° and 68°. The average high for August is 81° with an average low of 61°. 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 Riverside. See also: September | October | November.
