S
M
T
W
T
F
S
26
73°
53°
27
74°
53°
28
73°
55°
29
76°
61°
30
83°
61°
31
85°
60°
1
83°
56°
2
80°
59°
3
80°
61°
4
81°
60°
5
82°
61°
6
83°
58°
7
82°
57°
8
82°
51°
9
76°
52°
10
74°
52°
11
79°
54°
12
77°
51°
13
75°
51°
14
77°
59°
15
82°
60°
16
85°
62°
17
85°
54°
18
81°
52°
19
81°
52°
20
79°
54°
21
75°
61°
22
82°
56°
23
84°
53°
24
82°
54°
25
81°
58°
26
81°
57°
27
72°
55°
28
69°
49°
29
72°
51°
30
72°
52°
31
Hist. Avg.
76°
55°
1
Hist. Avg.
75°
55°
2
Hist. Avg.
75°
55°
3
Hist. Avg.
75°
55°
4
Hist. Avg.
75°
54°
5
Hist. Avg.
74°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
August Weather in Issaquah
Issaquah's August 2026 forecast shows daily high temperatures ranging from 69° to 85°, with overnight lows between 49° and 62°. The average high for August is 79° with an average low of 56°. 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 Issaquah. See also: September | October | November.
