S
M
T
W
T
F
S
26
80°
52°
27
73°
53°
28
77°
60°
29
77°
60°
30
83°
61°
31
84°
60°
1
75°
59°
2
73°
56°
3
75°
59°
4
83°
60°
5
77°
59°
6
74°
57°
7
75°
59°
8
74°
57°
9
79°
59°
10
83°
59°
11
81°
58°
12
74°
59°
13
78°
59°
14
83°
60°
15
83°
60°
16
82°
59°
17
84°
61°
18
84°
60°
19
79°
59°
20
81°
60°
21
83°
60°
22
83°
59°
23
82°
59°
24
80°
55°
25
80°
54°
26
76°
52°
27
77°
53°
28
81°
57°
29
82°
52°
30
83°
45°
31
75°
42°
1
67°
43°
2
68°
44°
3
71°
48°
4
79°
53°
5
79°
54°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Grantham
Grantham's August 2026 forecast shows daily high temperatures ranging from 67° to 84°, with overnight lows between 42° and 61°. The average high for August is 79° with an average low of 56°. 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 Grantham. See also: September | October | November.
