S
M
T
W
T
F
S
30
65°
53°
31
72°
48°
1
64°
51°
2
66°
53°
3
68°
48°
4
68°
48°
5
71°
50°
6
73°
47°
7
67°
49°
8
70°
50°
9
72°
50°
10
70°
51°
11
66°
52°
12
68°
52°
13
70°
50°
14
71°
51°
15
68°
50°
16
67°
52°
17
69°
51°
18
68°
52°
19
68°
51°
20
67°
48°
21
64°
52°
22
63°
51°
23
62°
50°
24
62°
52°
25
66°
52°
26
63°
51°
27
61°
51°
28
60°
48°
29
59°
46°
30
59°
48°
1
64°
50°
2
67°
51°
3
66°
50°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Friday Harbor
Friday Harbor's September 2026 forecast shows daily high temperatures ranging from 59° to 72°, with overnight lows between 46° and 52°. The average high for September is 66° with an average low of 50°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in Friday Harbor. See also: October | November | December.
