S
M
T
W
T
F
S
30
67°
52°
31
72°
53°
1
74°
53°
2
73°
50°
3
72°
44°
4
69°
47°
5
71°
42°
6
68°
41°
7
63°
43°
8
64°
49°
9
67°
46°
10
66°
41°
11
63°
47°
12
64°
45°
13
68°
46°
14
65°
47°
15
68°
39°
16
66°
40°
17
66°
40°
18
59°
39°
19
Hist. Avg.
61°
42°
20
Hist. Avg.
61°
41°
21
Hist. Avg.
60°
41°
22
Hist. Avg.
60°
41°
23
Hist. Avg.
59°
41°
24
Hist. Avg.
59°
40°
25
Hist. Avg.
59°
40°
26
Hist. Avg.
58°
40°
27
Hist. Avg.
58°
39°
28
Hist. Avg.
57°
39°
29
Hist. Avg.
57°
39°
30
Hist. Avg.
56°
38°
1
Hist. Avg.
56°
38°
2
Hist. Avg.
56°
38°
3
Hist. Avg.
55°
38°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Mountain Brook
Mountain Brook's September 2026 forecast shows daily high temperatures ranging from 59° to 74°, with overnight lows between 39° and 53°. The average high for September is 67° with an average low of 45°. 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 Brook. See also: October | November | December.
