S
M
T
W
T
F
S
30
78°
66°
31
78°
71°
1
80°
68°
2
73°
66°
3
86°
69°
4
86°
76°
5
81°
69°
6
74°
63°
7
80°
60°
8
82°
65°
9
80°
66°
10
88°
72°
11
79°
67°
12
77°
62°
13
80°
71°
14
77°
62°
15
70°
56°
16
76°
60°
17
80°
69°
18
83°
71°
19
70°
64°
20
72°
65°
21
72°
62°
22
69°
58°
23
70°
55°
24
66°
54°
25
70°
56°
26
64°
55°
27
67°
59°
28
63°
59°
29
71°
58°
30
76°
63°
1
71°
65°
2
79°
60°
3
71°
57°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in Oceanside
Oceanside's September 2026 forecast shows daily high temperatures ranging from 71° to 79°, with overnight lows between 57° and 65°. The average high for September is 74° with an average low of 61°. 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 Oceanside. See also: October | November | December.
