S
M
T
W
T
F
S
30
66°
51°
31
66°
52°
1
67°
54°
2
67°
52°
3
68°
50°
4
65°
51°
5
65°
53°
6
66°
49°
7
67°
52°
8
68°
50°
9
68°
51°
10
69°
51°
11
64°
52°
12
66°
48°
13
68°
51°
14
68°
49°
15
67°
46°
16
63°
49°
17
66°
47°
18
67°
47°
19
66°
52°
20
67°
53°
21
67°
52°
22
66°
52°
23
63°
49°
24
65°
50°
25
63°
51°
26
62°
49°
27
63°
50°
28
64°
49°
29
64°
48°
30
59°
45°
1
59°
48°
2
Hist. Avg.
58°
47°
3
Hist. Avg.
58°
47°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Fairfield
Fairfield's September 2026 forecast shows daily high temperatures ranging from 59° to 69°, with overnight lows between 45° and 54°. The average high for September is 65° with an average low of 50°. 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 Fairfield. See also: October | November | December.
