S
M
T
W
T
F
S
30
92°
70°
31
92°
69°
1
91°
70°
2
91°
70°
3
90°
71°
4
91°
70°
5
92°
71°
6
92°
70°
7
89°
71°
8
89°
70°
9
90°
71°
10
89°
70°
11
90°
69°
12
90°
70°
13
89°
70°
14
91°
68°
15
91°
70°
16
92°
70°
17
91°
68°
18
90°
67°
19
91°
69°
20
91°
69°
21
90°
68°
22
91°
69°
23
90°
68°
24
90°
68°
25
89°
66°
26
89°
67°
27
88°
66°
28
89°
67°
29
88°
65°
30
87°
66°
1
86°
65°
2
87°
65°
3
88°
66°
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 86° to 92°, with overnight lows between 65° and 71°. The average high for September is 90° with an average low of 69°. 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.
