S
M
T
W
T
F
S
30
96°
72°
31
99°
73°
1
100°
79°
2
100°
82°
3
99°
82°
4
100°
81°
5
101°
81°
6
90°
73°
7
87°
65°
8
93°
65°
9
93°
72°
10
80°
71°
11
83°
69°
12
92°
71°
13
86°
66°
14
88°
63°
15
98°
76°
16
94°
75°
17
99°
79°
18
98°
75°
19
97°
79°
20
92°
70°
21
73°
66°
22
72°
61°
23
70°
56°
24
70°
60°
25
72°
59°
26
73°
59°
27
78°
55°
28
78°
56°
29
82°
65°
30
79°
69°
1
79°
64°
2
77°
60°
3
74°
59°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Maryland Heights
Maryland Heights's September 2026 forecast shows daily high temperatures ranging from 73° to 82°, with overnight lows between 55° and 69°. The average high for September is 78° with an average low of 61°. 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 Maryland Heights. See also: October | November | December.