S
M
T
W
T
F
S
30
87°
75°
31
88°
76°
1
89°
75°
2
90°
76°
3
84°
76°
4
89°
77°
5
90°
75°
6
90°
75°
7
87°
73°
8
90°
75°
9
88°
76°
10
90°
77°
11
86°
76°
12
86°
76°
13
89°
76°
14
91°
75°
15
89°
77°
16
91°
77°
17
88°
72°
18
89°
70°
19
89°
71°
20
90°
74°
21
87°
74°
22
N/A
23
92°
72°
24
87°
67°
25
84°
66°
26
85°
64°
27
85°
68°
28
84°
69°
29
83°
68°
30
85°
72°
1
82°
68°
2
81°
67°
3
84°
72°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Port St. Joe
Port St. Joe's September 2026 forecast shows daily high temperatures ranging from 81° to 92°, with overnight lows between 64° and 72°. The average high for September is 85° with an average low of 68°. 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 Port St. Joe. See also: October | November | December.
