S
M
T
W
T
F
S
30
90°
69°
31
87°
67°
1
87°
65°
2
88°
65°
3
88°
68°
4
90°
66°
5
91°
64°
6
85°
64°
7
85°
66°
8
90°
69°
9
91°
63°
10
84°
62°
11
87°
65°
12
87°
61°
13
83°
60°
14
82°
59°
15
83°
60°
16
83°
60°
17
87°
61°
18
88°
61°
19
89°
65°
20
Hist. Avg.
84°
61°
21
Hist. Avg.
84°
60°
22
Hist. Avg.
83°
60°
23
Hist. Avg.
83°
60°
24
Hist. Avg.
83°
59°
25
Hist. Avg.
82°
59°
26
Hist. Avg.
82°
58°
27
Hist. Avg.
82°
58°
28
Hist. Avg.
81°
58°
29
Hist. Avg.
81°
57°
30
Hist. Avg.
80°
57°
1
Hist. Avg.
80°
56°
2
Hist. Avg.
80°
56°
3
Hist. Avg.
80°
56°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in St. Jo
St. Jo's September 2026 forecast shows daily high temperatures ranging from 82° to 91°, with overnight lows between 59° and 69°. The average high for September is 87° with an average low of 64°. 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. Jo. See also: October | November | December.
