S
M
T
W
T
F
S
30
83°
61°
31
84°
61°
1
84°
60°
2
83°
60°
3
84°
53°
4
78°
51°
5
75°
53°
6
76°
59°
7
81°
59°
8
81°
57°
9
82°
58°
10
76°
57°
11
81°
56°
12
81°
58°
13
80°
58°
14
79°
57°
15
81°
57°
16
80°
49°
17
76°
56°
18
78°
52°
19
74°
49°
20
73°
47°
21
68°
45°
22
68°
52°
23
69°
49°
24
69°
46°
25
67°
44°
26
67°
44°
27
68°
50°
28
74°
51°
29
75°
48°
30
69°
46°
1
66°
49°
2
66°
41°
3
64°
43°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Stillwater
Stillwater's September 2026 forecast shows daily high temperatures ranging from 64° to 84°, with overnight lows between 41° and 61°. The average high for September is 75° with an average low of 52°. 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 Stillwater. See also: October | November | December.
