S
M
T
W
T
F
S
26
63°
39°
27
61°
41°
28
70°
39°
29
77°
39°
30
81°
39°
1
81°
45°
2
77°
50°
3
73°
51°
4
61°
49°
5
73°
54°
6
85°
57°
7
84°
50°
8
81°
47°
9
87°
51°
10
91°
50°
11
90°
52°
12
88°
54°
13
91°
54°
14
89°
51°
15
84°
50°
16
78°
44°
17
80°
46°
18
72°
41°
19
74°
44°
20
80°
48°
21
82°
50°
22
81°
48°
23
80°
48°
24
83°
50°
25
82°
50°
26
83°
49°
27
83°
50°
28
82°
50°
29
83°
49°
30
83°
50°
31
84°
51°
1
84°
51°
2
85°
52°
3
86°
51°
4
85°
51°
5
85°
50°
6
83°
49°
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 61° to 91°, with overnight lows between 41° and 57°. The average high for May is 82° with an average low of 50°. 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.
