S
M
T
W
T
F
S
26
90°
80°
27
91°
81°
28
90°
82°
29
90°
81°
30
89°
82°
31
90°
82°
1
91°
81°
2
91°
82°
3
90°
82°
4
91°
81°
5
90°
80°
6
90°
81°
7
91°
82°
8
90°
81°
9
91°
80°
10
90°
80°
11
91°
81°
12
90°
81°
13
91°
80°
14
91°
82°
15
90°
81°
16
91°
81°
17
91°
80°
18
90°
80°
19
91°
81°
20
90°
78°
21
91°
80°
22
90°
78°
23
89°
79°
24
90°
80°
25
91°
79°
26
91°
80°
27
90°
79°
28
89°
79°
29
90°
80°
30
89°
81°
31
90°
80°
1
90°
79°
2
89°
81°
3
Hist. Avg.
90°
80°
4
Hist. Avg.
90°
80°
5
Hist. Avg.
90°
80°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Key West
Key West's August 2026 forecast shows daily high temperatures ranging from 89° to 91°, with overnight lows between 78° and 82°. The average high for August is 90° with an average low of 80°. 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 Key West. See also: September | October | November.
