S
M
T
W
T
F
S
30
65°
46°
31
66°
48°
1
65°
54°
2
63°
54°
3
63°
53°
4
64°
53°
5
63°
51°
6
64°
47°
7
63°
45°
8
64°
46°
9
65°
45°
10
68°
46°
11
64°
52°
12
61°
45°
13
60°
50°
14
62°
54°
15
Hist. Avg.
61°
42°
16
Hist. Avg.
60°
42°
17
Hist. Avg.
60°
42°
18
Hist. Avg.
60°
41°
19
Hist. Avg.
60°
41°
20
Hist. Avg.
59°
41°
21
Hist. Avg.
59°
41°
22
Hist. Avg.
59°
41°
23
Hist. Avg.
58°
41°
24
Hist. Avg.
58°
40°
25
Hist. Avg.
58°
40°
26
Hist. Avg.
57°
40°
27
Hist. Avg.
57°
40°
28
Hist. Avg.
57°
40°
29
Hist. Avg.
56°
40°
30
Hist. Avg.
56°
39°
1
Hist. Avg.
56°
39°
2
Hist. Avg.
55°
39°
3
Hist. Avg.
55°
39°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Mill Bay
Mill Bay's September 2026 forecast shows daily high temperatures ranging from 60° to 68°, with overnight lows between 45° and 54°. The average high for September is 64° 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 September weather will actually feel in Mill Bay. See also: October | November | December.
