S
M
T
W
T
F
S
30
99°
73°
31
99°
72°
1
97°
74°
2
97°
71°
3
81°
72°
4
95°
75°
5
95°
72°
6
96°
73°
7
N/A
8
96°
74°
9
95°
75°
10
96°
74°
11
96°
74°
12
97°
74°
13
96°
73°
14
96°
73°
15
92°
69°
16
91°
71°
17
92°
70°
18
90°
67°
19
90°
64°
20
84°
65°
21
87°
64°
22
91°
70°
23
90°
69°
24
89°
69°
25
84°
68°
26
88°
68°
27
88°
67°
28
87°
68°
29
87°
68°
30
84°
63°
1
79°
57°
2
77°
57°
3
77°
55°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Fairfield
Fairfield's September 2026 forecast shows daily high temperatures ranging from 77° to 97°, with overnight lows between 55° and 75°. The average high for September is 89° with an average low of 68°. 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.
