S
M
T
W
T
F
S
30
61°
49°
31
60°
51°
1
61°
52°
2
60°
50°
3
56°
48°
4
55°
46°
5
54°
47°
6
55°
46°
7
54°
45°
8
54°
45°
9
55°
46°
10
53°
45°
11
53°
45°
12
54°
46°
13
53°
47°
14
54°
48°
15
54°
49°
16
53°
45°
17
55°
45°
18
54°
46°
19
52°
44°
20
53°
44°
21
51°
45°
22
51°
44°
23
52°
44°
24
51°
43°
25
51°
43°
26
52°
41°
27
51°
43°
28
51°
43°
29
52°
44°
30
51°
45°
1
50°
47°
2
51°
47°
3
53°
46°
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 50° to 61°, with overnight lows between 41° and 52°. The average high for September is 54° 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.
