S
M
T
W
T
F
S
26
92°
58°
27
88°
60°
28
92°
59°
29
89°
55°
30
91°
61°
31
91°
63°
1
100°
59°
2
83°
61°
3
64°
43°
4
72°
39°
5
80°
45°
6
82°
52°
7
87°
49°
8
86°
56°
9
81°
54°
10
85°
54°
11
82°
52°
12
75°
54°
13
59°
53°
14
69°
55°
15
76°
54°
16
81°
52°
17
77°
49°
18
81°
51°
19
82°
49°
20
88°
55°
21
86°
55°
22
85°
59°
23
90°
58°
24
77°
51°
25
80°
47°
26
87°
54°
27
90°
58°
28
79°
57°
29
82°
55°
30
69°
44°
31
76°
49°
1
84°
55°
2
82°
50°
3
77°
47°
4
77°
48°
5
76°
50°
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 69° to 84°, with overnight lows between 44° and 55°. The average high for August is 77° with an average low of 49°. 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.
