S
M
T
W
T
F
S
30
90°
71°
31
93°
70°
1
97°
70°
2
97°
73°
3
99°
73°
4
97°
72°
5
97°
72°
6
95°
72°
7
79°
72°
8
86°
68°
9
90°
64°
10
93°
64°
11
93°
68°
12
82°
72°
13
91°
68°
14
93°
70°
15
82°
72°
16
88°
68°
17
90°
66°
18
95°
68°
19
91°
70°
20
88°
68°
21
91°
66°
22
82°
68°
23
73°
63°
24
70°
59°
25
76°
50°
26
81°
49°
27
80°
51°
28
79°
54°
29
82°
55°
30
81°
59°
1
83°
62°
2
82°
62°
3
81°
63°
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 76° to 83°, with overnight lows between 49° and 63°. The average high for September is 81° with an average low of 56°. 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.
