S
M
T
W
T
F
S
26
87°
76°
27
87°
76°
28
88°
75°
29
88°
77°
30
89°
77°
31
90°
76°
1
87°
76°
2
88°
75°
3
89°
77°
4
90°
77°
5
90°
76°
6
89°
77°
7
89°
77°
8
90°
76°
9
85°
75°
10
89°
75°
11
90°
74°
12
90°
76°
13
89°
75°
14
88°
74°
15
89°
75°
16
88°
74°
17
88°
74°
18
90°
73°
19
90°
74°
20
91°
73°
21
91°
73°
22
90°
74°
23
89°
74°
24
88°
75°
25
88°
74°
26
89°
73°
27
87°
73°
28
87°
74°
29
88°
73°
30
89°
73°
31
91°
74°
1
90°
75°
2
89°
74°
3
88°
75°
4
87°
74°
5
88°
74°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Sebastian
Sebastian's August 2026 forecast shows daily high temperatures ranging from 85° to 91°, with overnight lows between 73° and 77°. The average high for August is 89° with an average low of 75°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how August weather will actually feel in Sebastian. See also: September | October | November.