S
M
T
W
T
F
S
26
76°
54°
27
68°
56°
28
70°
59°
29
65°
49°
30
64°
38°
1
58°
40°
2
58°
36°
3
65°
34°
4
79°
52°
5
70°
48°
6
61°
42°
7
63°
36°
8
71°
48°
9
75°
54°
10
72°
52°
11
73°
43°
12
78°
42°
13
70°
50°
14
68°
39°
15
73°
43°
16
77°
61°
17
85°
64°
18
84°
68°
19
85°
65°
20
69°
58°
21
65°
56°
22
65°
61°
23
71°
60°
24
76°
63°
25
76°
64°
26
76°
63°
27
75°
62°
28
77°
63°
29
78°
62°
30
76°
62°
31
77°
62°
1
78°
63°
2
78°
61°
3
77°
55°
4
77°
61°
5
76°
61°
6
78°
60°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
May Weather in Eureka
Eureka's May 2026 forecast shows daily high temperatures ranging from 65° to 78°, with overnight lows between 55° and 64°. The average high for May is 75° with an average low of 61°. 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 Eureka. See also: June | July | August.
