S
M
T
W
T
F
S
30
77°
45°
31
85°
46°
1
85°
56°
2
75°
44°
3
72°
49°
4
71°
46°
5
72°
45°
6
80°
50°
7
77°
52°
8
79°
48°
9
81°
49°
10
83°
51°
11
83°
49°
12
78°
47°
13
79°
48°
14
80°
48°
15
78°
45°
16
77°
49°
17
71°
46°
18
70°
42°
19
70°
43°
20
75°
50°
21
72°
45°
22
77°
49°
23
72°
43°
24
68°
40°
25
68°
38°
26
69°
43°
27
77°
47°
28
77°
47°
29
78°
46°
30
78°
47°
1
77°
46°
2
77°
46°
3
76°
45°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Sunnyside
Sunnyside's September 2026 forecast shows daily high temperatures ranging from 68° to 83°, with overnight lows between 38° and 52°. The average high for September is 76° with an average low of 46°. 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 Sunnyside. See also: October | November | December.
