S
M
T
W
T
F
S
26
87°
58°
27
88°
58°
28
82°
57°
29
88°
58°
30
88°
58°
31
89°
57°
1
85°
55°
2
78°
54°
3
84°
57°
4
88°
58°
5
88°
58°
6
87°
57°
7
78°
56°
8
84°
56°
9
86°
57°
10
87°
56°
11
86°
57°
12
80°
56°
13
77°
56°
14
79°
55°
15
79°
55°
16
83°
54°
17
81°
55°
18
83°
55°
19
84°
56°
20
84°
55°
21
81°
56°
22
87°
52°
23
84°
44°
24
80°
42°
25
73°
41°
26
70°
44°
27
72°
44°
28
71°
43°
29
73°
51°
30
79°
46°
31
81°
44°
1
72°
51°
2
81°
48°
3
80°
48°
4
73°
50°
5
79°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in Lewistown
Lewistown's August 2026 forecast shows daily high temperatures ranging from 70° to 89°, with overnight lows between 41° and 58°. The average high for August is 81° with an average low of 53°. 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 Lewistown. See also: September | October | November.
