S
M
T
W
T
F
S
26
85°
52°
27
88°
51°
28
92°
53°
29
92°
54°
30
92°
53°
31
94°
52°
1
98°
54°
2
98°
58°
3
97°
58°
4
89°
55°
5
85°
57°
6
84°
56°
7
87°
54°
8
88°
55°
9
91°
53°
10
87°
49°
11
84°
52°
12
84°
54°
13
78°
55°
14
77°
54°
15
81°
55°
16
83°
54°
17
83°
55°
18
84°
56°
19
85°
57°
20
87°
55°
21
90°
56°
22
91°
56°
23
92°
57°
24
93°
53°
25
89°
54°
26
87°
55°
27
88°
57°
28
86°
55°
29
88°
55°
30
84°
52°
31
85°
55°
1
84°
53°
2
84°
53°
3
85°
52°
4
83°
53°
5
84°
55°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Calistoga
Calistoga's August 2026 forecast shows daily high temperatures ranging from 77° to 93°, with overnight lows between 52° and 57°. The average high for August is 85° with an average low of 55°. 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 Calistoga. See also: September | October | November.