S
M
T
W
T
F
S
30
79°
54°
31
78°
58°
1
79°
57°
2
81°
60°
3
82°
51°
4
79°
50°
5
77°
57°
6
81°
51°
7
75°
57°
8
78°
59°
9
81°
58°
10
81°
58°
11
80°
57°
12
78°
57°
13
80°
53°
14
78°
53°
15
73°
49°
16
76°
49°
17
74°
47°
18
73°
48°
19
73°
47°
20
69°
48°
21
69°
47°
22
73°
41°
23
66°
46°
24
65°
49°
25
64°
51°
26
73°
52°
27
68°
51°
28
68°
47°
29
72°
41°
30
72°
37°
1
62°
36°
2
59°
35°
3
57°
35°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in St. Peter
St. Peter's September 2026 forecast shows daily high temperatures ranging from 57° to 82°, with overnight lows between 35° and 60°. The average high for September is 74° with an average low of 50°. 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 St. Peter. See also: October | November | December.
