S
M
T
W
T
F
S
26
88°
76°
27
91°
74°
28
91°
74°
29
92°
75°
30
93°
74°
31
90°
75°
1
91°
74°
2
89°
74°
3
92°
75°
4
92°
75°
5
91°
74°
6
91°
75°
7
89°
74°
8
89°
74°
9
90°
75°
10
92°
74°
11
92°
75°
12
91°
75°
13
89°
74°
14
89°
74°
15
91°
75°
16
90°
74°
17
89°
74°
18
89°
75°
19
88°
76°
20
89°
74°
21
90°
75°
22
92°
74°
23
92°
73°
24
90°
74°
25
92°
76°
26
91°
77°
27
90°
76°
28
89°
76°
29
89°
77°
30
90°
76°
31
92°
75°
1
90°
73°
2
89°
73°
3
90°
74°
4
89°
73°
5
88°
72°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Lake Forest
Lake Forest's August 2026 forecast shows daily high temperatures ranging from 88° to 93°, with overnight lows between 72° and 77°. The average high for August is 90° 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 Lake Forest. See also: September | October | November.
