S
M
T
W
T
F
S
30
72°
49°
31
73°
44°
1
69°
43°
2
68°
44°
3
66°
47°
4
67°
49°
5
67°
49°
6
68°
48°
7
71°
49°
8
71°
49°
9
70°
48°
10
71°
45°
11
70°
41°
12
65°
42°
13
63°
40°
14
65°
39°
15
62°
40°
16
63°
39°
17
62°
40°
18
60°
42°
19
62°
40°
20
67°
38°
21
61°
40°
22
62°
43°
23
62°
42°
24
65°
39°
25
62°
38°
26
58°
37°
27
58°
37°
28
57°
36°
29
57°
38°
30
58°
41°
1
61°
42°
2
62°
42°
3
62°
41°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in St. Joseph's
St. Joseph's's September 2026 forecast shows daily high temperatures ranging from 57° to 73°, with overnight lows between 36° and 49°. The average high for September is 64° with an average low of 42°. 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. Joseph's. See also: October | November | December.
