Click on a day for an hourly weather forecast
The temperatures in Oceanside in September are comfortable with low of 19°C and and high up to 26°C.
You can expect a few rainy days in Oceanside during September, but usually the weather is comfortable in September.
Our weather forecast can give you a great sense of what weather to expect in Oceanside in September 2025.
If you’re planning to visit Oceanside in the near future, we highly recommend that you review the 14 day weather forecast for Oceanside before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 19° / 12° | 2 | 29 | 0 | 37 mm | Good | Oceanside in January |
| February | 18° / 11° | 2 | 27 | 0 | 39 mm | Good | Oceanside in February |
| March | 18° / 12° | 1 | 30 | 0 | 26 mm | Good | Oceanside in March |
| April | 19° / 13° | 1 | 30 | 0 | 13 mm | Good | Oceanside in April |
| May | 20° / 14° | 0 | 31 | 0 | 14 mm | Good | Oceanside in May |
| June | 22° / 16° | 0 | 30 | 0 | 7 mm | Good | Oceanside in June |
| July | 24° / 18° | 1 | 30 | 0 | 26 mm | Perfect | Oceanside in July |
| August | 25° / 19° | 1 | 30 | 0 | 14 mm | Perfect | Oceanside in August |
| September | 26° / 19° | 1 | 29 | 0 | 14 mm | Perfect | Oceanside in September |
| October | 24° / 17° | 1 | 30 | 0 | 12 mm | Perfect | Oceanside in October |
| November | 21° / 15° | 1 | 29 | 0 | 24 mm | Good | Oceanside in November |
| December | 18° / 12° | 2 | 29 | 0 | 39 mm | Good | Oceanside in December |