S
M
T
W
T
F
S
26
83°
61°
27
75°
55°
28
70°
50°
29
84°
59°
30
78°
61°
1
69°
58°
2
64°
43°
3
73°
44°
4
80°
52°
5
83°
58°
6
82°
65°
7
76°
49°
8
71°
50°
9
77°
58°
10
78°
57°
11
79°
61°
12
77°
59°
13
79°
60°
14
80°
60°
15
81°
58°
16
77°
56°
17
78°
58°
18
79°
62°
19
81°
62°
20
83°
63°
21
78°
60°
22
80°
56°
23
76°
55°
24
77°
57°
25
78°
59°
26
79°
58°
27
77°
57°
28
78°
58°
29
79°
60°
30
79°
61°
31
80°
63°
1
82°
66°
2
81°
65°
3
80°
66°
4
81°
65°
5
84°
66°
6
85°
67°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Washington
Washington's May 2026 forecast shows daily high temperatures ranging from 64° to 85°, with overnight lows between 43° and 67°. 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 Washington. See also: June | July | August.
