S
M
T
W
T
F
S
28
68°
49°
29
66°
51°
30
64°
52°
1
64°
51°
2
59°
49°
3
68°
54°
4
67°
51°
5
74°
47°
6
76°
47°
7
70°
52°
8
71°
50°
9
67°
53°
10
67°
52°
11
68°
50°
12
68°
51°
13
73°
52°
14
75°
53°
15
74°
52°
16
73°
52°
17
72°
52°
18
73°
53°
19
72°
51°
20
73°
52°
21
70°
53°
22
73°
54°
23
75°
54°
24
75°
53°
25
74°
53°
26
69°
52°
27
72°
54°
28
72°
54°
29
69°
53°
30
69°
53°
31
72°
54°
1
71°
53°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
July Weather in San Juan Island
San Juan Island's July 2026 forecast shows daily high temperatures ranging from 67° to 75°, with overnight lows between 50° and 54°. The average high for July is 71° with an average low of 53°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how July weather will actually feel in San Juan Island. See also: August | September | October.
