S
M
T
W
T
F
S
30
60°
51°
31
59°
52°
1
56°
51°
2
58°
51°
3
60°
50°
4
60°
49°
5
59°
48°
6
60°
49°
7
60°
45°
8
55°
46°
9
56°
45°
10
60°
48°
11
59°
50°
12
55°
50°
13
55°
49°
14
56°
45°
15
56°
45°
16
53°
46°
17
53°
45°
18
54°
47°
19
54°
42°
20
52°
44°
21
53°
44°
22
52°
45°
23
52°
44°
24
51°
44°
25
52°
43°
26
51°
43°
27
52°
44°
28
51°
43°
29
52°
44°
30
51°
47°
1
52°
44°
2
51°
45°
3
53°
42°
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 51° to 60°, with overnight lows between 42° and 52°. The average high for September is 55° 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.
