S
M
T
W
T
F
S
30
86°
76°
31
89°
75°
1
89°
75°
2
86°
76°
3
88°
76°
4
93°
78°
5
94°
75°
6
93°
74°
7
89°
73°
8
87°
73°
9
90°
75°
10
90°
75°
11
90°
75°
12
90°
74°
13
90°
73°
14
89°
72°
15
90°
75°
16
88°
78°
17
89°
78°
18
87°
72°
19
88°
72°
20
89°
73°
21
87°
73°
22
86°
72°
23
87°
73°
24
88°
75°
25
85°
74°
26
86°
66°
27
87°
63°
28
86°
69°
29
87°
72°
30
86°
74°
1
87°
76°
2
86°
75°
3
89°
76°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Sebastian
Sebastian's September 2026 forecast shows daily high temperatures ranging from 86° to 89°, with overnight lows between 69° and 76°. The average high for September is 87° with an average low of 74°. 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 Sebastian. See also: October | November | December.
