S
M
T
W
T
F
S
26
100°
78°
27
101°
79°
28
100°
79°
29
100°
78°
30
99°
79°
31
100°
79°
1
99°
78°
2
100°
79°
3
100°
79°
4
101°
78°
5
101°
80°
6
100°
79°
7
101°
79°
8
101°
80°
9
100°
80°
10
101°
79°
11
101°
80°
12
100°
79°
13
101°
78°
14
100°
79°
15
101°
78°
16
100°
79°
17
95°
75°
18
95°
74°
19
94°
75°
20
96°
74°
21
95°
76°
22
96°
74°
23
97°
71°
24
96°
71°
25
96°
75°
26
97°
70°
27
91°
69°
28
95°
68°
29
93°
68°
30
95°
69°
31
97°
70°
1
97°
74°
2
96°
71°
3
96°
72°
4
95°
73°
5
96°
73°
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 91° to 101°, with overnight lows between 68° and 80°. The average high for August is 98° with an average low of 76°. 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.
