September weather in Oceanside, CA
The average temperature in Oceanside in September is 68.5°F (59.2°F–77.8°F). Average precipitation: 0.13 inches.
September is a fall month in Oceanside, and is warmer than the annual average of 61°F. Daily temperatures swing about 18.6°F between overnight low and afternoon high. Expect about 2 days with precipitation. Daylight averages about 12h 12m. For travel, September is one of the best months of the year to visit.
Avg High
77.8°F
Avg Low
59.2°F
Precipitation
0.13 in
Daylight
12h 12m
September records in Oceanside
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 91.0°F (2017) | 54.0°F (2000) | 0.00 in (1999) |
| September 2 | 91.9°F (2017) | 52.0°F (2012) | 0.01 in (2023) |
| September 3 | 93.0°F (2007) | 51.1°F (1999) | 0.00 in (1999) |
| September 4 | 96.1°F (2022) | 51.1°F (2000) | 0.00 in (1999) |
| September 5 | 100.9°F (2004) | 50.0°F (2000) | 0.01 in (2010) |
| September 6 | 102.0°F (2020) | 46.9°F (2005) | 0.03 in (2002) |
| September 7 | 93.9°F (2024) | 52.0°F (2000) | 0.00 in (1999) |
| September 8 | 97.0°F (2024) | 55.0°F (1999) | 0.00 in (1999) |
| September 9 | 95.0°F (2015) | 52.0°F (2000) | 0.39 in (2022) |
| September 10 | 98.1°F (2015) | 48.0°F (2000) | 0.00 in (1999) |
| September 11 | 90.0°F (2015) | 46.0°F (2000) | 0.01 in (2007) |
| September 12 | 90.0°F (2015) | 50.0°F (2011) | 0.01 in (2022) |
| September 13 | 86.0°F (2000) | 53.1°F (2020) | 0.00 in (1999) |
| September 14 | 97.0°F (2012) | 52.0°F (1999) | 0.01 in (2007) |
| September 15 | 100.9°F (2012) | 50.0°F (2016) | 1.14 in (2015) |
| September 16 | 100.0°F (2014) | 48.9°F (2016) | 0.01 in (2007) |
| September 17 | 91.0°F (2014) | 48.9°F (2006) | 0.03 in (2025) |
| September 18 | 90.0°F (2020) | 46.9°F (2006) | 0.09 in (2025) |
| September 19 | 82.9°F (2020) | 48.0°F (2006) | 0.00 in (1999) |
| September 20 | 93.9°F (2015) | 46.9°F (1999) | 0.18 in (2016) |
| September 21 | 90.0°F (2004) | 46.0°F (2007) | 0.06 in (2016) |
| September 22 | 89.1°F (2004) | 48.9°F (2004) | 0.13 in (2007) |
| September 23 | 93.0°F (2009) | 48.9°F (2004) | 0.01 in (2007) |
| September 24 | 88.0°F (2009) | 48.0°F (2004) | 0.02 in (2021) |
| September 25 | 91.0°F (2016) | 48.0°F (2017) | 0.01 in (2010) |
| September 26 | 104.0°F (2016) | 46.9°F (2017) | 0.01 in (2007) |
| September 27 | 105.1°F (2010) | 46.9°F (2013) | 0.01 in (2006) |
| September 28 | 90.0°F (2016) | 45.0°F (2005) | 0.05 in (2007) |
| September 29 | 91.9°F (1999) | 46.0°F (2013) | 0.24 in (2002) |
| September 30 | 95.0°F (2020) | 46.0°F (2013) | 0.77 in (2010) |