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°
51°
6
70°
51°
7
64°
47°
8
63°
40°
9
59°
46°
10
71°
45°
11
63°
47°
12
67°
39°
13
67°
49°
14
60°
46°
15
64°
46°
16
75°
59°
17
82°
58°
18
86°
60°
19
91°
63°
20
77°
51°
21
72°
49°
22
71°
52°
23
69°
49°
24
69°
49°
25
70°
51°
26
74°
50°
27
70°
53°
28
71°
50°
29
69°
52°
30
70°
55°
31
75°
52°
1
70°
50°
2
70°
48°
3
69°
48°
4
70°
49°
5
72°
57°
6
78°
58°
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 91°, with overnight lows between 46° and 63°. The average high for May is 72° 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 Lehigh Valley. See also: June | July | August.