S
M
T
W
T
F
S
26
59°
44°
27
72°
38°
28
63°
43°
29
62°
49°
30
68°
48°
1
66°
42°
2
64°
48°
3
63°
44°
4
72°
56°
5
82°
61°
6
69°
53°
7
61°
43°
8
61°
46°
9
64°
50°
10
71°
55°
11
66°
51°
12
67°
50°
13
68°
53°
14
67°
54°
15
70°
53°
16
72°
55°
17
74°
54°
18
78°
59°
19
77°
59°
20
77°
60°
21
78°
59°
22
75°
52°
23
70°
51°
24
69°
53°
25
70°
53°
26
72°
54°
27
71°
53°
28
71°
55°
29
72°
53°
30
72°
56°
31
73°
63°
1
77°
62°
2
74°
58°
3
74°
61°
4
78°
63°
5
77°
61°
6
80°
64°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Thornton
Thornton's May 2026 forecast shows daily high temperatures ranging from 61° to 82°, with overnight lows between 43° and 64°. The average high for May is 72° with an average low of 55°. 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 Thornton. See also: June | July | August.
