S
M
T
W
T
F
S
26
84°
52°
27
82°
54°
28
81°
52°
29
85°
54°
30
86°
53°
31
85°
52°
1
84°
52°
2
84°
50°
3
83°
51°
4
81°
53°
5
82°
54°
6
86°
54°
7
85°
53°
8
86°
53°
9
86°
50°
10
84°
50°
11
82°
51°
12
82°
53°
13
84°
52°
14
86°
50°
15
83°
49°
16
81°
49°
17
81°
50°
18
83°
55°
19
84°
55°
20
88°
53°
21
87°
49°
22
81°
49°
23
82°
53°
24
81°
54°
25
84°
53°
26
84°
51°
27
81°
50°
28
81°
52°
29
85°
51°
30
86°
53°
31
Hist. Avg.
88°
54°
1
Hist. Avg.
88°
54°
2
Hist. Avg.
88°
54°
3
Hist. Avg.
88°
54°
4
Hist. Avg.
88°
53°
5
Hist. Avg.
87°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
August Weather in Guerneville
Guerneville's August 2026 forecast shows daily high temperatures ranging from 81° to 88°, with overnight lows between 49° and 55°. The average high for August is 84° with an average low of 52°. 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 Guerneville. See also: September | October | November.
