S
M
T
W
T
F
S
30
89°
72°
31
83°
70°
1
87°
62°
2
86°
62°
3
83°
62°
4
85°
63°
5
88°
69°
6
87°
70°
7
92°
71°
8
88°
67°
9
87°
66°
10
87°
66°
11
90°
69°
12
90°
67°
13
89°
68°
14
88°
64°
15
91°
68°
16
90°
68°
17
90°
67°
18
87°
64°
19
83°
63°
20
85°
63°
21
88°
64°
22
88°
65°
23
87°
65°
24
84°
62°
25
80°
59°
26
80°
59°
27
79°
58°
28
80°
58°
29
82°
60°
30
82°
62°
1
81°
60°
2
84°
62°
3
87°
65°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Brea Chem
Brea Chem's September 2026 forecast shows daily high temperatures ranging from 79° to 92°, with overnight lows between 58° and 71°. The average high for September is 86° with an average low of 64°. 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 Brea Chem. See also: October | November | December.
