S
M
T
W
T
F
S
26
66°
32°
27
70°
41°
28
60°
39°
29
48°
36°
30
42°
34°
1
39°
30°
2
47°
23°
3
58°
32°
4
75°
39°
5
51°
37°
6
46°
29°
7
45°
30°
8
59°
29°
9
57°
38°
10
50°
31°
11
50°
27°
12
53°
31°
13
48°
37°
14
63°
38°
15
73°
42°
16
76°
55°
17
64°
47°
18
81°
65°
19
77°
37°
20
52°
29°
21
60°
33°
22
56°
45°
23
61°
45°
24
64°
49°
25
68°
48°
26
72°
49°
27
69°
50°
28
70°
50°
29
73°
49°
30
71°
49°
31
72°
45°
1
65°
50°
2
66°
51°
3
63°
50°
4
64°
47°
5
65°
51°
6
69°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Lewiston
Lewiston's May 2026 forecast shows daily high temperatures ranging from 52° to 81°, with overnight lows between 29° and 65°. The average high for May is 67° with an average low of 47°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how May weather will actually feel in Lewiston. See also: June | July | August.
