S
M
T
W
T
F
S
26
61°
41°
27
71°
35°
28
60°
39°
29
62°
48°
30
61°
45°
1
63°
36°
2
59°
44°
3
60°
42°
4
72°
40°
5
82°
59°
6
66°
43°
7
61°
40°
8
61°
41°
9
61°
48°
10
71°
50°
11
64°
43°
12
60°
40°
13
65°
46°
14
65°
48°
15
70°
50°
16
71°
50°
17
69°
47°
18
68°
48°
19
74°
51°
20
75°
53°
21
75°
52°
22
73°
46°
23
67°
44°
24
66°
45°
25
67°
46°
26
68°
46°
27
68°
47°
28
69°
47°
29
68°
46°
30
68°
47°
31
70°
56°
1
72°
53°
2
70°
48°
3
71°
53°
4
75°
55°
5
72°
52°
6
76°
56°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Lehigh Valley
Lehigh Valley's May 2026 forecast shows daily high temperatures ranging from 60° to 82°, with overnight lows between 40° and 59°. The average high for May is 69° with an average low of 48°. 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 Lehigh Valley. See also: June | July | August.