S
M
T
W
T
F
S
30
77°
53°
31
79°
55°
1
80°
54°
2
79°
51°
3
76°
51°
4
77°
49°
5
75°
47°
6
76°
47°
7
76°
48°
8
77°
47°
9
75°
45°
10
74°
46°
11
75°
48°
12
77°
51°
13
79°
45°
14
74°
43°
15
71°
42°
16
72°
42°
17
72°
43°
18
73°
44°
19
78°
45°
20
77°
44°
21
77°
45°
22
78°
49°
23
79°
50°
24
78°
49°
25
75°
50°
26
75°
46°
27
72°
47°
28
72°
48°
29
73°
46°
30
66°
45°
1
67°
46°
2
70°
45°
3
68°
37°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Blue Mountain
Blue Mountain's September 2026 forecast shows daily high temperatures ranging from 66° to 80°, with overnight lows between 37° and 55°. The average high for September is 75° with an average low of 47°. 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 Blue Mountain. See also: October | November | December.
