S
M
T
W
T
F
S
26
68°
40°
27
59°
42°
28
57°
50°
29
68°
47°
30
76°
44°
1
77°
50°
2
79°
51°
3
82°
48°
4
80°
51°
5
67°
52°
6
60°
49°
7
67°
53°
8
62°
49°
9
71°
50°
10
69°
47°
11
74°
48°
12
83°
49°
13
62°
52°
14
62°
50°
15
52°
44°
16
58°
44°
17
66°
44°
18
67°
45°
19
65°
52°
20
69°
48°
21
75°
45°
22
77°
46°
23
71°
48°
24
69°
55°
25
63°
48°
26
67°
48°
27
76°
49°
28
76°
52°
29
68°
47°
30
65°
45°
31
66°
46°
1
72°
49°
2
76°
49°
3
78°
51°
4
76°
49°
5
69°
48°
6
65°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Sumas
Sumas's May 2026 forecast shows daily high temperatures ranging from 63° to 78°, with overnight lows between 45° and 55°. The average high for May is 70° with an average low of 49°. 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 Sumas. See also: June | July | August.
