S
M
T
W
T
F
S
26
90°
75°
27
93°
79°
28
91°
81°
29
90°
80°
30
87°
84°
31
89°
84°
1
87°
83°
2
88°
82°
3
90°
76°
4
89°
78°
5
90°
77°
6
89°
78°
7
89°
78°
8
90°
76°
9
88°
78°
10
91°
76°
11
90°
78°
12
91°
76°
13
87°
78°
14
88°
79°
15
88°
78°
16
87°
78°
17
87°
79°
18
88°
79°
19
88°
78°
20
89°
78°
21
86°
76°
22
87°
76°
23
85°
78°
24
86°
78°
25
87°
76°
26
88°
76°
27
87°
77°
28
87°
77°
29
88°
76°
30
88°
78°
31
87°
77°
1
86°
78°
2
87°
78°
3
87°
77°
4
88°
77°
5
85°
76°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Upper Captiva
Upper Captiva's August 2026 forecast shows daily high temperatures ranging from 85° to 91°, with overnight lows between 76° and 84°. The average high for August 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 August weather will actually feel in Upper Captiva. See also: September | October | November.