S
M
T
W
T
F
S
30
81°
54°
31
82°
54°
1
82°
58°
2
80°
56°
3
82°
56°
4
85°
57°
5
83°
55°
6
83°
57°
7
86°
57°
8
86°
56°
9
84°
55°
10
83°
56°
11
88°
54°
12
89°
57°
13
88°
57°
14
87°
54°
15
87°
53°
16
84°
50°
17
75°
51°
18
78°
50°
19
81°
53°
20
79°
52°
21
84°
49°
22
82°
49°
23
81°
48°
24
81°
51°
25
82°
52°
26
82°
45°
27
72°
46°
28
70°
45°
29
79°
48°
30
79°
49°
1
80°
37°
2
76°
40°
3
68°
40°
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 68° to 89°, with overnight lows between 37° and 58°. The average high for September is 81° with an average low of 51°. 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.
