S
M
T
W
T
F
S
26
87°
69°
27
88°
70°
28
89°
69°
29
88°
68°
30
86°
67°
31
78°
64°
1
81°
68°
2
88°
70°
3
89°
69°
4
89°
69°
5
88°
68°
6
87°
69°
7
87°
66°
8
87°
59°
9
86°
57°
10
79°
63°
11
80°
58°
12
81°
59°
13
79°
59°
14
80°
60°
15
80°
65°
16
81°
61°
17
82°
58°
18
79°
57°
19
81°
57°
20
84°
56°
21
85°
58°
22
85°
64°
23
86°
64°
24
86°
66°
25
87°
65°
26
87°
62°
27
85°
54°
28
79°
55°
29
77°
54°
30
78°
56°
31
79°
53°
1
77°
54°
2
76°
53°
3
76°
53°
4
81°
58°
5
79°
56°
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 76° to 89°, with overnight lows between 53° and 70°. The average high for August is 83° with an average low of 61°. 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.
