S
M
T
W
T
F
S
30
75°
52°
31
75°
56°
1
73°
56°
2
74°
52°
3
74°
54°
4
75°
54°
5
73°
53°
6
72°
50°
7
73°
52°
8
81°
54°
9
82°
56°
10
82°
59°
11
81°
58°
12
82°
59°
13
83°
59°
14
79°
49°
15
75°
52°
16
74°
57°
17
80°
58°
18
81°
53°
19
80°
52°
20
79°
56°
21
76°
57°
22
78°
56°
23
79°
54°
24
77°
56°
25
76°
57°
26
78°
57°
27
78°
56°
28
69°
52°
29
67°
54°
30
69°
53°
1
66°
51°
2
64°
48°
3
63°
49°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Happy Valley
Happy Valley's September 2026 forecast shows daily high temperatures ranging from 63° to 83°, with overnight lows between 48° and 59°. The average high for September is 76° with an average low of 54°. 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 Happy Valley. See also: October | November | December.
