S
M
T
W
T
F
S
26
82°
64°
27
82°
57°
28
84°
67°
29
84°
65°
30
80°
59°
1
77°
60°
2
68°
54°
3
72°
53°
4
77°
54°
5
81°
61°
6
86°
65°
7
83°
61°
8
84°
60°
9
83°
60°
10
85°
59°
11
83°
58°
12
86°
63°
13
87°
64°
14
87°
64°
15
85°
58°
16
80°
58°
17
80°
59°
18
81°
58°
19
84°
60°
20
87°
64°
21
88°
65°
22
89°
66°
23
88°
66°
24
89°
67°
25
89°
67°
26
90°
68°
27
90°
67°
28
86°
67°
29
83°
68°
30
84°
68°
31
85°
67°
1
84°
69°
2
84°
69°
3
85°
68°
4
85°
69°
5
86°
69°
6
86°
70°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Ashburn-Sycamore
Ashburn-Sycamore's May 2026 forecast shows daily high temperatures ranging from 68° to 90°, with overnight lows between 53° and 70°. The average high for May is 84° with an average low of 63°. 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 Ashburn-Sycamore. See also: June | July | August.
