S
M
T
W
T
F
S
30
93°
63°
31
96°
68°
1
99°
69°
2
100°
72°
3
101°
72°
4
100°
72°
5
102°
71°
6
89°
59°
7
88°
58°
8
95°
68°
9
100°
71°
10
86°
63°
11
86°
62°
12
90°
65°
13
93°
67°
14
90°
62°
15
90°
67°
16
89°
66°
17
88°
65°
18
81°
57°
19
76°
63°
20
79°
62°
21
85°
62°
22
80°
61°
23
81°
61°
24
85°
62°
25
85°
63°
26
84°
62°
27
85°
62°
28
84°
61°
29
84°
62°
30
83°
62°
1
80°
57°
2
80°
51°
3
70°
48°
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 70° to 102°, with overnight lows between 48° and 71°. The average high for September is 86° with an average low of 62°. 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.
