S
M
T
W
T
F
S
26
88°
71°
27
89°
68°
28
89°
68°
29
91°
69°
30
90°
68°
31
88°
70°
1
89°
71°
2
90°
71°
3
93°
72°
4
92°
71°
5
91°
70°
6
88°
70°
7
88°
69°
8
90°
69°
9
92°
70°
10
88°
70°
11
91°
71°
12
89°
71°
13
87°
70°
14
87°
71°
15
88°
71°
16
89°
70°
17
92°
71°
18
91°
68°
19
87°
70°
20
87°
69°
21
89°
69°
22
90°
68°
23
87°
66°
24
86°
68°
25
90°
67°
26
87°
69°
27
90°
67°
28
90°
64°
29
84°
64°
30
85°
65°
31
85°
64°
1
86°
64°
2
86°
65°
3
87°
65°
4
88°
66°
5
88°
68°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Waterloo
Waterloo's August 2026 forecast shows daily high temperatures ranging from 84° to 93°, with overnight lows between 64° and 72°. The average high for August is 89° with an average low of 69°. 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 Waterloo. See also: September | October | November.
