S
M
T
W
T
F
S
26
55°
45°
27
72°
41°
28
63°
50°
29
59°
55°
30
66°
45°
1
68°
37°
2
59°
43°
3
63°
37°
4
79°
45°
5
84°
55°
6
72°
55°
7
66°
46°
8
73°
43°
9
75°
55°
10
81°
50°
11
63°
46°
12
71°
53°
13
73°
50°
14
63°
48°
15
72°
48°
16
85°
63°
17
88°
64°
18
91°
66°
19
90°
61°
20
80°
59°
21
79°
59°
22
78°
61°
23
79°
60°
24
78°
61°
25
79°
56°
26
80°
61°
27
81°
62°
28
81°
62°
29
80°
61°
30
81°
63°
31
82°
62°
1
81°
60°
2
74°
56°
3
74°
58°
4
77°
62°
5
75°
63°
6
81°
63°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Ashburn
Ashburn's May 2026 forecast shows daily high temperatures ranging from 63° to 91°, with overnight lows between 48° and 66°. The average high for May is 79° with an average low of 59°. 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. See also: June | July | August.