S
M
T
W
T
F
S
31
71°
61°
1
71°
62°
2
70°
61°
3
69°
62°
4
73°
61°
5
73°
60°
6
72°
62°
7
71°
62°
8
70°
62°
9
69°
62°
10
68°
63°
11
67°
62°
12
69°
65°
13
72°
63°
14
73°
63°
15
73°
64°
16
70°
63°
17
69°
62°
18
71°
64°
19
70°
64°
20
71°
63°
21
69°
65°
22
66°
64°
23
68°
62°
24
70°
63°
25
70°
63°
26
71°
64°
27
73°
65°
28
73°
65°
29
72°
64°
30
74°
66°
1
72°
65°
2
73°
66°
3
74°
67°
4
73°
66°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
June Weather in Costa Mesa
Costa Mesa's June 2026 forecast shows daily high temperatures ranging from 66° to 74°, with overnight lows between 60° and 67°. The average high for June is 71° with an average low of 64°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how June weather will actually feel in Costa Mesa. See also: July | August | September.
