S
M
T
W
T
F
S
30
85°
68°
31
83°
63°
1
81°
62°
2
77°
63°
3
77°
63°
4
78°
64°
5
77°
62°
6
76°
62°
7
76°
63°
8
77°
64°
9
76°
63°
10
74°
61°
11
75°
62°
12
77°
63°
13
75°
62°
14
76°
61°
15
73°
62°
16
74°
60°
17
72°
59°
18
73°
60°
19
76°
63°
20
Hist. Avg.
76°
63°
21
Hist. Avg.
75°
63°
22
Hist. Avg.
75°
62°
23
Hist. Avg.
75°
62°
24
Hist. Avg.
74°
62°
25
Hist. Avg.
74°
61°
26
Hist. Avg.
74°
61°
27
Hist. Avg.
73°
60°
28
Hist. Avg.
73°
60°
29
Hist. Avg.
72°
60°
30
Hist. Avg.
72°
59°
1
Hist. Avg.
72°
59°
2
Hist. Avg.
71°
58°
3
Hist. Avg.
71°
58°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
*Temporarily Unavailable
September Weather in Sunnyside
Sunnyside's September 2026 forecast shows daily high temperatures ranging from 72° to 85°, with overnight lows between 59° and 68°. The average high for September is 77° with an average low of 62°. 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.
