S
M
T
W
T
F
S
30
74°
48°
31
72°
47°
1
72°
48°
2
73°
49°
3
71°
49°
4
70°
48°
5
73°
49°
6
72°
48°
7
70°
46°
8
69°
45°
9
69°
47°
10
70°
48°
11
68°
45°
12
68°
44°
13
70°
44°
14
71°
50°
15
71°
50°
16
73°
49°
17
73°
43°
18
68°
42°
19
71°
47°
20
72°
44°
21
66°
42°
22
67°
46°
23
68°
47°
24
69°
48°
25
70°
45°
26
69°
39°
27
68°
40°
28
61°
39°
29
60°
38°
30
61°
38°
1
61°
38°
2
Hist. Avg.
63°
45°
3
Hist. Avg.
62°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Saint Joseph
Saint Joseph's September 2026 forecast shows daily high temperatures ranging from 60° to 74°, with overnight lows between 38° and 50°. The average high for September is 69° with an average low of 45°. 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 Saint Joseph. See also: October | November | December.
