S
M
T
W
T
F
S
30
81°
55°
31
77°
54°
1
75°
58°
2
75°
55°
3
76°
56°
4
75°
54°
5
74°
54°
6
73°
57°
7
73°
55°
8
74°
54°
9
75°
53°
10
74°
53°
11
73°
54°
12
72°
52°
13
74°
54°
14
73°
56°
15
77°
57°
16
79°
56°
17
80°
57°
18
79°
55°
19
78°
56°
20
Hist. Avg.
74°
52°
21
Hist. Avg.
74°
51°
22
Hist. Avg.
73°
51°
23
Hist. Avg.
73°
50°
24
Hist. Avg.
72°
50°
25
Hist. Avg.
72°
50°
26
Hist. Avg.
72°
49°
27
Hist. Avg.
71°
49°
28
Hist. Avg.
71°
48°
29
Hist. Avg.
70°
48°
30
Hist. Avg.
70°
48°
1
Hist. Avg.
69°
47°
2
Hist. Avg.
69°
47°
3
Hist. Avg.
68°
46°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Rockford
Rockford's September 2026 forecast shows daily high temperatures ranging from 72° to 81°, with overnight lows between 52° and 58°. The average high for September is 76° with an average low of 55°. 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.
