S
M
T
W
T
F
S
30
75°
54°
31
78°
54°
1
77°
49°
2
73°
48°
3
69°
48°
4
69°
49°
5
70°
48°
6
71°
56°
7
77°
57°
8
80°
50°
9
75°
48°
10
71°
47°
11
71°
55°
12
72°
46°
13
74°
46°
14
68°
44°
15
68°
48°
16
69°
53°
17
73°
44°
18
68°
45°
19
67°
45°
20
71°
43°
21
66°
50°
22
65°
52°
23
75°
52°
24
75°
50°
25
73°
51°
26
73°
51°
27
75°
49°
28
74°
49°
29
71°
48°
30
72°
50°
1
73°
38°
2
73°
37°
3
61°
39°
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 61° to 80°, with overnight lows between 37° and 57°. The average high for September is 72° with an average low of 48°. 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.
