S
M
T
W
T
F
S
30
82°
70°
31
85°
71°
1
87°
66°
2
82°
65°
3
81°
65°
4
81°
64°
5
82°
64°
6
82°
67°
7
83°
64°
8
83°
69°
9
85°
69°
10
85°
68°
11
84°
67°
12
85°
69°
13
85°
69°
14
84°
68°
15
85°
68°
16
85°
66°
17
82°
67°
18
82°
67°
19
81°
66°
20
81°
66°
21
82°
64°
22
81°
58°
23
77°
64°
24
74°
64°
25
Hist. Avg.
77°
61°
26
Hist. Avg.
77°
60°
27
Hist. Avg.
76°
60°
28
Hist. Avg.
76°
60°
29
Hist. Avg.
76°
59°
30
Hist. Avg.
75°
59°
1
Hist. Avg.
75°
58°
2
Hist. Avg.
75°
58°
3
Hist. Avg.
74°
58°
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 74° to 87°, with overnight lows between 58° and 71°. The average high for September is 83° with an average low of 66°. 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.
