S
M
T
W
T
F
S
30
78°
66°
31
78°
71°
1
79°
66°
2
75°
69°
3
83°
73°
4
87°
67°
5
82°
64°
6
75°
64°
7
76°
64°
8
76°
61°
9
75°
63°
10
78°
64°
11
77°
64°
12
78°
62°
13
77°
61°
14
75°
60°
15
72°
59°
16
72°
64°
17
74°
56°
18
70°
55°
19
70°
55°
20
71°
58°
21
74°
62°
22
77°
63°
23
78°
62°
24
77°
60°
25
75°
58°
26
75°
59°
27
76°
61°
28
76°
60°
29
75°
57°
30
69°
53°
1
65°
51°
2
68°
56°
3
73°
59°
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 65° to 87°, with overnight lows between 51° and 73°. The average high for September is 75° 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.
