S
M
T
W
T
F
S
26
68°
43°
27
57°
47°
28
56°
46°
29
66°
47°
30
75°
48°
1
72°
52°
2
73°
56°
3
81°
54°
4
81°
53°
5
74°
50°
6
72°
51°
7
70°
51°
8
65°
51°
9
71°
50°
10
75°
52°
11
74°
54°
12
71°
52°
13
68°
50°
14
69°
51°
15
66°
48°
16
61°
53°
17
68°
48°
18
61°
47°
19
61°
45°
20
62°
45°
21
71°
52°
22
71°
51°
23
67°
48°
24
72°
54°
25
71°
51°
26
69°
49°
27
72°
54°
28
73°
55°
29
74°
54°
30
74°
55°
31
75°
56°
1
74°
55°
2
73°
54°
3
73°
54°
4
72°
52°
5
72°
52°
6
71°
50°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in SeaTac
SeaTac's May 2026 forecast shows daily high temperatures ranging from 61° to 81°, with overnight lows between 45° and 56°. The average high for May is 71° with an average low of 52°. 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 SeaTac. See also: June | July | August.
