S
M
T
W
T
F
S
30
78°
66°
31
78°
71°
1
80°
68°
2
73°
66°
3
86°
69°
4
86°
76°
5
81°
69°
6
74°
63°
7
80°
60°
8
82°
65°
9
80°
66°
10
88°
72°
11
79°
67°
12
77°
62°
13
80°
71°
14
77°
62°
15
73°
64°
16
80°
70°
17
82°
71°
18
83°
66°
19
73°
67°
20
76°
66°
21
72°
61°
22
71°
60°
23
70°
59°
24
69°
60°
25
74°
60°
26
73°
61°
27
72°
60°
28
71°
58°
29
76°
60°
30
70°
56°
1
68°
57°
2
70°
61°
3
74°
58°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Mill Basin
Mill Basin's September 2026 forecast shows daily high temperatures ranging from 68° to 83°, with overnight lows between 56° and 71°. The average high for September is 74° with an average low of 62°. 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 Basin. See also: October | November | December.
