S
M
T
W
T
F
S
30
88°
69°
31
86°
68°
1
86°
67°
2
85°
66°
3
85°
67°
4
86°
64°
5
85°
64°
6
85°
65°
7
84°
66°
8
85°
66°
9
85°
65°
10
84°
66°
11
83°
65°
12
84°
65°
13
84°
64°
14
83°
65°
15
83°
65°
16
82°
64°
17
83°
66°
18
83°
65°
19
82°
62°
20
81°
63°
21
78°
65°
22
80°
58°
23
81°
57°
24
75°
57°
25
76°
59°
26
79°
62°
27
75°
60°
28
74°
60°
29
73°
58°
30
74°
59°
1
75°
62°
2
78°
53°
3
76°
52°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Mill Creek
Mill Creek's September 2026 forecast shows daily high temperatures ranging from 73° to 88°, with overnight lows between 52° and 69°. The average high for September is 81° with an average low of 63°. 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 Creek. See also: October | November | December.
