S
M
T
W
T
F
S
30
83°
53°
31
84°
53°
1
83°
50°
2
83°
52°
3
84°
54°
4
78°
48°
5
79°
50°
6
78°
48°
7
86°
52°
8
83°
51°
9
75°
48°
10
77°
47°
11
77°
49°
12
82°
50°
13
82°
48°
14
81°
51°
15
77°
51°
16
73°
50°
17
74°
47°
18
79°
49°
19
76°
45°
20
72°
45°
21
81°
49°
22
74°
45°
23
73°
43°
24
75°
44°
25
70°
39°
26
71°
40°
27
74°
42°
28
78°
43°
29
76°
35°
30
71°
34°
1
67°
36°
2
69°
38°
3
73°
34°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Frederick
Frederick's September 2026 forecast shows daily high temperatures ranging from 67° to 86°, with overnight lows between 34° and 54°. The average high for September is 77° with an average low of 46°. 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 Frederick. See also: October | November | December.
