S
M
T
W
T
F
S
30
78°
56°
31
78°
61°
1
77°
62°
2
78°
62°
3
79°
61°
4
80°
62°
5
83°
62°
6
84°
63°
7
84°
62°
8
83°
61°
9
80°
60°
10
81°
61°
11
82°
61°
12
81°
60°
13
76°
60°
14
76°
58°
15
73°
59°
16
73°
58°
17
74°
58°
18
77°
57°
19
78°
58°
20
78°
56°
21
81°
57°
22
82°
49°
23
79°
47°
24
72°
54°
25
70°
52°
26
69°
56°
27
77°
54°
28
77°
55°
29
80°
54°
30
80°
53°
1
78°
52°
2
77°
53°
3
78°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Westminster
Westminster's September 2026 forecast shows daily high temperatures ranging from 69° to 84°, with overnight lows between 47° and 63°. The average high for September is 78° 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 Westminster. See also: October | November | December.
