S
M
T
W
T
F
S
26
57°
40°
27
62°
37°
28
64°
40°
29
66°
43°
30
63°
42°
1
62°
42°
2
65°
38°
3
73°
38°
4
65°
47°
5
67°
43°
6
56°
39°
7
70°
34°
8
69°
49°
9
78°
53°
10
76°
50°
11
82°
47°
12
89°
46°
13
85°
57°
14
80°
52°
15
80°
53°
16
79°
54°
17
85°
50°
18
66°
42°
19
66°
38°
20
68°
40°
21
79°
35°
22
70°
48°
23
74°
47°
24
74°
54°
25
71°
51°
26
66°
48°
27
74°
49°
28
78°
48°
29
72°
47°
30
72°
51°
31
73°
48°
1
76°
49°
2
74°
53°
3
78°
52°
4
76°
52°
5
75°
49°
6
76°
46°
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 66° to 78°, with overnight lows between 46° and 54°. The average high for May is 74° with an average low of 50°. 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.
