S
M
T
W
T
F
S
26
66°
48°
27
68°
50°
28
72°
52°
29
74°
55°
30
73°
54°
1
75°
53°
2
66°
50°
3
66°
48°
4
67°
48°
5
69°
55°
6
75°
55°
7
76°
56°
8
75°
52°
9
67°
50°
10
68°
50°
11
69°
56°
12
71°
56°
13
73°
57°
14
79°
58°
15
79°
59°
16
78°
58°
17
74°
57°
18
71°
53°
19
70°
50°
20
71°
58°
21
72°
58°
22
75°
52°
23
75°
54°
24
77°
54°
25
76°
53°
26
75°
53°
27
76°
57°
28
76°
59°
29
80°
60°
30
80°
54°
31
79°
55°
1
78°
57°
2
81°
60°
3
83°
63°
4
84°
63°
5
85°
62°
6
85°
63°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Hillsboro
Hillsboro's May 2026 forecast shows daily high temperatures ranging from 66° to 85°, with overnight lows between 48° and 63°. The average high for May is 75° 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 Hillsboro. See also: June | July | August.
