S
M
T
W
T
F
S
26
77°
46°
27
63°
57°
28
62°
51°
29
62°
43°
30
62°
37°
1
56°
43°
2
57°
39°
3
66°
39°
4
75°
50°
5
55°
48°
6
59°
43°
7
63°
39°
8
64°
48°
9
75°
50°
10
68°
52°
11
70°
46°
12
84°
45°
13
70°
44°
14
70°
39°
15
74°
50°
16
75°
61°
17
85°
61°
18
77°
61°
19
78°
58°
20
70°
50°
21
68°
48°
22
72°
54°
23
78°
58°
24
77°
58°
25
83°
54°
26
80°
58°
27
86°
60°
28
85°
58°
29
78°
57°
30
82°
53°
31
79°
57°
1
80°
53°
2
82°
54°
3
80°
56°
4
79°
59°
5
79°
57°
6
81°
59°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Monticello
Monticello's May 2026 forecast shows daily high temperatures ranging from 78° to 86°, with overnight lows between 53° and 60°. The average high for May is 81° with an average low of 57°. 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 Monticello. See also: June | July | August.
