S
M
T
W
T
F
S
30
75°
53°
31
75°
51°
1
77°
56°
2
75°
57°
3
79°
64°
4
76°
60°
5
71°
56°
6
74°
51°
7
78°
54°
8
73°
59°
9
71°
59°
10
72°
55°
11
66°
49°
12
76°
46°
13
79°
61°
14
65°
44°
15
66°
41°
16
76°
54°
17
69°
53°
18
67°
43°
19
61°
39°
20
64°
44°
21
60°
45°
22
61°
45°
23
67°
43°
24
69°
43°
25
73°
48°
26
70°
53°
27
68°
50°
28
61°
47°
29
63°
49°
30
71°
50°
1
69°
51°
2
66°
49°
3
65°
48°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Brownsburg-Chatham
Brownsburg-Chatham's September 2026 forecast shows daily high temperatures ranging from 61° to 73°, with overnight lows between 43° and 53°. The average high for September is 68° with an average low of 49°. 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 Brownsburg-Chatham. See also: October | November | December.
