S
M
T
W
T
F
S
26
70°
56°
27
70°
57°
28
71°
55°
29
69°
55°
30
72°
54°
31
70°
56°
1
72°
56°
2
71°
57°
3
75°
57°
4
76°
58°
5
76°
59°
6
75°
57°
7
76°
59°
8
75°
57°
9
76°
56°
10
75°
55°
11
75°
55°
12
76°
57°
13
76°
57°
14
75°
56°
15
74°
59°
16
73°
57°
17
72°
56°
18
72°
55°
19
71°
56°
20
72°
59°
21
72°
56°
22
73°
55°
23
75°
56°
24
76°
56°
25
77°
58°
26
76°
59°
27
76°
58°
28
75°
57°
29
74°
56°
30
73°
55°
31
72°
54°
1
73°
55°
2
74°
56°
3
77°
56°
4
77°
57°
5
76°
58°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in San Mateo
San Mateo's August 2026 forecast shows daily high temperatures ranging from 69° to 77°, with overnight lows between 54° and 59°. The average high for August is 74° with an average low of 57°. 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 San Mateo. See also: September | October | November.
