S
M
T
W
T
F
S
26
64°
40°
27
64°
37°
28
63°
42°
29
70°
42°
30
75°
43°
1
80°
44°
2
83°
51°
3
84°
53°
4
85°
52°
5
83°
50°
6
87°
56°
7
81°
51°
8
76°
51°
9
78°
51°
10
82°
52°
11
81°
53°
12
86°
54°
13
83°
53°
14
84°
54°
15
81°
50°
16
74°
48°
17
74°
50°
18
68°
44°
19
66°
44°
20
68°
45°
21
75°
49°
22
79°
55°
23
74°
51°
24
78°
54°
25
81°
55°
26
78°
53°
27
76°
54°
28
76°
54°
29
77°
51°
30
81°
54°
31
82°
56°
1
83°
57°
2
82°
56°
3
83°
58°
4
82°
57°
5
82°
55°
6
81°
56°
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 66° to 87°, with overnight lows between 44° and 58°. The average high for May is 79° with an average low of 52°. 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.
