S
M
T
W
T
F
S
30
58°
42°
31
58°
41°
1
60°
39°
2
62°
44°
3
64°
50°
4
64°
52°
5
62°
50°
6
61°
52°
7
61°
51°
8
60°
48°
9
59°
47°
10
57°
48°
11
58°
47°
12
56°
48°
13
55°
46°
14
53°
43°
15
53°
41°
16
55°
41°
17
51°
42°
18
52°
43°
19
53°
44°
20
52°
43°
21
53°
41°
22
52°
38°
23
53°
42°
24
50°
39°
25
49°
35°
26
48°
36°
27
47°
35°
28
46°
35°
29
47°
33°
30
45°
34°
1
45°
40°
2
47°
41°
3
50°
40°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Mountain View
Mountain View's September 2026 forecast shows daily high temperatures ranging from 45° to 64°, with overnight lows between 33° and 52°. The average high for September is 54° with an average low of 43°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Mountain View. See also: October | November | December.
