S
M
T
W
T
F
S
30
78°
58°
31
79°
62°
1
83°
57°
2
79°
55°
3
78°
53°
4
76°
55°
5
78°
56°
6
82°
59°
7
84°
63°
8
86°
63°
9
86°
55°
10
78°
54°
11
78°
61°
12
82°
57°
13
84°
52°
14
76°
50°
15
75°
52°
16
76°
57°
17
79°
59°
18
82°
51°
19
76°
58°
20
80°
58°
21
82°
57°
22
82°
58°
23
81°
58°
24
78°
57°
25
80°
57°
26
80°
56°
27
81°
56°
28
80°
55°
29
81°
55°
30
80°
56°
1
80°
51°
2
79°
45°
3
78°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Rockford
Rockford's September 2026 forecast shows daily high temperatures ranging from 75° to 86°, with overnight lows between 45° and 63°. The average high for September is 80° with an average low of 56°. 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 Rockford. See also: October | November | December.
