S
M
T
W
T
F
S
30
80°
60°
31
80°
59°
1
79°
55°
2
73°
55°
3
72°
54°
4
72°
52°
5
73°
52°
6
75°
58°
7
78°
58°
8
72°
57°
9
72°
57°
10
75°
56°
11
78°
56°
12
78°
57°
13
77°
57°
14
78°
47°
15
70°
46°
16
68°
47°
17
70°
46°
18
68°
45°
19
67°
46°
20
68°
48°
21
74°
51°
22
74°
52°
23
75°
45°
24
74°
42°
25
68°
43°
26
67°
45°
27
72°
50°
28
72°
50°
29
71°
43°
30
70°
42°
1
65°
40°
2
65°
43°
3
69°
47°
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 65° to 80°, with overnight lows between 40° and 60°. The average high for September is 73° with an average low of 50°. 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.
