S
M
T
W
T
F
S
26
86°
62°
27
82°
61°
28
80°
58°
29
79°
57°
30
78°
56°
31
80°
58°
1
86°
60°
2
86°
59°
3
82°
55°
4
81°
54°
5
85°
58°
6
86°
57°
7
80°
55°
8
81°
56°
9
80°
62°
10
86°
63°
11
89°
63°
12
89°
64°
13
88°
61°
14
90°
59°
15
89°
57°
16
88°
54°
17
87°
57°
18
82°
58°
19
79°
53°
20
79°
53°
21
80°
55°
22
78°
51°
23
78°
55°
24
80°
56°
25
84°
59°
26
85°
60°
27
86°
57°
28
86°
61°
29
86°
60°
30
84°
60°
31
85°
59°
1
83°
55°
2
82°
54°
3
82°
55°
4
80°
57°
5
78°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Lake Oswego
Lake Oswego's August 2026 forecast shows daily high temperatures ranging from 78° to 90°, with overnight lows between 51° and 64°. The average high for August is 83° with an average low of 58°. 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 Lake Oswego. See also: September | October | November.
