S
M
T
W
T
F
S
30
83°
60°
31
83°
65°
1
84°
60°
2
82°
58°
3
81°
56°
4
80°
58°
5
81°
58°
6
82°
63°
7
85°
66°
8
88°
66°
9
88°
61°
10
81°
58°
11
83°
64°
12
83°
64°
13
86°
56°
14
79°
55°
15
79°
57°
16
81°
56°
17
83°
55°
18
82°
59°
19
84°
59°
20
85°
58°
21
85°
61°
22
84°
61°
23
82°
60°
24
80°
61°
25
78°
60°
26
83°
61°
27
82°
59°
28
82°
59°
29
81°
58°
30
82°
60°
1
82°
59°
2
81°
50°
3
81°
50°
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 78° to 88°, with overnight lows between 50° and 66°. The average high for September is 82° 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.
