S
M
T
W
T
F
S
30
96°
74°
31
92°
75°
1
89°
76°
2
95°
74°
3
96°
74°
4
91°
75°
5
92°
74°
6
94°
77°
7
96°
75°
8
92°
74°
9
92°
73°
10
91°
75°
11
91°
72°
12
92°
73°
13
90°
71°
14
91°
70°
15
90°
70°
16
91°
72°
17
92°
70°
18
91°
70°
19
86°
67°
20
86°
71°
21
90°
71°
22
90°
71°
23
89°
70°
24
89°
70°
25
88°
69°
26
88°
70°
27
87°
69°
28
87°
69°
29
85°
68°
30
86°
69°
1
86°
64°
2
81°
60°
3
79°
60°
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 79° to 96°, with overnight lows between 60° and 77°. The average high for September is 89° with an average low of 70°. 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.
