S
M
T
W
T
F
S
30
84°
65°
31
83°
58°
1
79°
57°
2
76°
58°
3
77°
59°
4
78°
58°
5
79°
58°
6
75°
59°
7
75°
57°
8
76°
61°
9
76°
57°
10
74°
56°
11
75°
57°
12
76°
55°
13
75°
56°
14
74°
56°
15
73°
57°
16
75°
54°
17
74°
53°
18
72°
54°
19
Hist. Avg.
78°
57°
20
Hist. Avg.
78°
56°
21
Hist. Avg.
77°
56°
22
Hist. Avg.
77°
56°
23
Hist. Avg.
77°
55°
24
Hist. Avg.
76°
55°
25
Hist. Avg.
76°
54°
26
Hist. Avg.
75°
54°
27
Hist. Avg.
75°
53°
28
Hist. Avg.
75°
53°
29
Hist. Avg.
74°
52°
30
Hist. Avg.
74°
52°
1
Hist. Avg.
73°
52°
2
Hist. Avg.
73°
51°
3
Hist. Avg.
73°
51°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Fairfax
Fairfax's September 2026 forecast shows daily high temperatures ranging from 72° to 84°, with overnight lows between 53° and 65°. The average high for September is 76° with an average low of 57°. 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 Fairfax. See also: October | November | December.
