S
M
T
W
T
F
S
30
88°
77°
31
88°
79°
1
84°
77°
2
86°
79°
3
88°
79°
4
89°
80°
5
88°
77°
6
88°
77°
7
90°
77°
8
90°
80°
9
86°
74°
10
90°
79°
11
89°
79°
12
90°
76°
13
90°
79°
14
84°
77°
15
88°
78°
16
86°
77°
17
90°
81°
18
90°
81°
19
90°
81°
20
89°
79°
21
N/A
22
86°
79°
23
87°
78°
24
87°
78°
25
86°
78°
26
87°
77°
27
87°
77°
28
88°
78°
29
87°
77°
30
86°
78°
1
86°
79°
2
87°
80°
3
86°
80°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Capitol Hill
Capitol Hill's September 2026 forecast shows daily high temperatures ranging from 86° to 88°, with overnight lows between 77° and 80°. The average high for September is 87° with an average low of 78°. 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 Capitol Hill. See also: October | November | December.
