S
M
T
W
T
F
S
30
73°
63°
31
72°
59°
1
72°
57°
2
70°
63°
3
76°
67°
4
72°
55°
5
73°
54°
6
80°
62°
7
76°
57°
8
67°
51°
9
65°
52°
10
66°
55°
11
68°
53°
12
67°
52°
13
67°
54°
14
68°
55°
15
69°
56°
16
64°
45°
17
65°
48°
18
65°
46°
19
66°
50°
20
68°
50°
21
68°
51°
22
67°
50°
23
67°
50°
24
65°
48°
25
67°
50°
26
66°
49°
27
66°
46°
28
65°
47°
29
65°
49°
30
66°
48°
1
60°
43°
2
59°
43°
3
60°
42°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Brentwood
Brentwood's September 2026 forecast shows daily high temperatures ranging from 59° to 80°, with overnight lows between 42° and 67°. The average high for September is 67° with an average low of 51°. 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 Brentwood. See also: October | November | December.
