S
M
T
W
T
F
S
30
86°
56°
31
75°
57°
1
78°
57°
2
79°
57°
3
78°
58°
4
79°
55°
5
84°
54°
6
82°
52°
7
92°
54°
8
97°
68°
9
98°
68°
10
103°
66°
11
89°
62°
12
86°
59°
13
85°
58°
14
88°
59°
15
87°
60°
16
90°
59°
17
92°
61°
18
93°
60°
19
86°
56°
20
89°
60°
21
81°
58°
22
81°
56°
23
84°
57°
24
85°
56°
25
84°
56°
26
80°
58°
27
87°
59°
28
87°
60°
29
88°
60°
30
87°
59°
1
87°
59°
2
88°
58°
3
87°
59°
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 80° to 103°, with overnight lows between 52° and 68°. The average high for September is 88° with an average low of 59°. 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.
