S
M
T
W
T
F
S
26
96°
73°
27
94°
74°
28
86°
70°
29
85°
67°
30
83°
63°
31
75°
63°
1
82°
63°
2
81°
62°
3
83°
60°
4
74°
62°
5
76°
51°
6
82°
61°
7
83°
64°
8
84°
66°
9
85°
69°
10
86°
63°
11
85°
63°
12
81°
61°
13
82°
62°
14
81°
61°
15
80°
61°
16
82°
64°
17
86°
58°
18
88°
66°
19
87°
65°
20
85°
65°
21
86°
66°
22
87°
66°
23
86°
65°
24
84°
65°
25
81°
64°
26
77°
62°
27
78°
60°
28
84°
63°
29
84°
63°
30
85°
64°
31
86°
64°
1
85°
63°
2
85°
64°
3
86°
64°
4
85°
63°
5
85°
62°
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 74° to 88°, with overnight lows between 51° and 69°. The average high for August is 83° with an average low of 63°. 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.
