S
M
T
W
T
F
S
30
93°
76°
31
91°
79°
1
87°
80°
2
88°
78°
3
88°
79°
4
91°
79°
5
89°
80°
6
88°
80°
7
89°
79°
8
88°
80°
9
89°
81°
10
90°
80°
11
88°
80°
12
89°
79°
13
90°
79°
14
89°
80°
15
90°
77°
16
86°
78°
17
86°
78°
18
88°
78°
19
87°
77°
20
87°
78°
21
88°
78°
22
87°
76°
23
88°
77°
24
88°
76°
25
86°
77°
26
88°
77°
27
88°
76°
28
87°
77°
29
86°
76°
30
86°
75°
1
85°
76°
2
85°
76°
3
86°
75°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in St. Petersburg
St. Petersburg's September 2026 forecast shows daily high temperatures ranging from 85° to 91°, with overnight lows between 75° and 81°. The average high for September is 88° with an average low of 78°. 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. Petersburg. See also: October | November | December.
