S
M
T
W
T
F
S
26
94°
74°
27
88°
74°
28
83°
73°
29
83°
66°
30
83°
63°
31
79°
62°
1
N/A
2
81°
60°
3
81°
62°
4
82°
63°
5
74°
59°
6
78°
63°
7
82°
65°
8
83°
65°
9
87°
64°
10
82°
62°
11
82°
63°
12
80°
62°
13
83°
62°
14
82°
61°
15
77°
63°
16
83°
65°
17
87°
66°
18
86°
66°
19
86°
64°
20
84°
64°
21
85°
65°
22
86°
65°
23
85°
64°
24
83°
64°
25
84°
62°
26
78°
62°
27
82°
61°
28
84°
60°
29
83°
61°
30
84°
62°
31
84°
62°
1
85°
61°
2
84°
62°
3
85°
62°
4
84°
61°
5
83°
61°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
August Weather in Grinnell
Grinnell's August 2026 forecast shows daily high temperatures ranging from 74° to 87°, with overnight lows between 59° and 66°. 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 Grinnell. See also: September | October | November.
