S
M
T
W
T
F
S
26
59°
38°
27
69°
37°
28
66°
37°
29
66°
48°
30
65°
47°
1
66°
44°
2
63°
47°
3
61°
44°
4
75°
44°
5
85°
55°
6
73°
58°
7
67°
50°
8
69°
45°
9
73°
49°
10
80°
47°
11
61°
46°
12
68°
41°
13
77°
49°
14
68°
51°
15
68°
50°
16
84°
45°
17
89°
63°
18
97°
59°
19
98°
72°
20
97°
69°
21
69°
60°
22
66°
53°
23
55°
52°
24
61°
53°
25
74°
57°
26
81°
60°
27
81°
65°
28
79°
59°
29
78°
54°
30
68°
47°
31
77°
45°
1
76°
50°
2
78°
46°
3
84°
55°
4
88°
51°
5
92°
57°
6
92°
64°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Allentown
Allentown's May 2026 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for May is ° with an average low of °. 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 Allentown. See also: June | July | August.
