Oceanside weather in September: Oceanside, California: normal highs, lows, rain and records for September
Oceanside in September has a normal high of 78°F and a normal low of 59°F, a daily mean of 69°F, falling from 79°F on the 1st to 76°F by the 30th. Measurable precipitation falls on 2 days in a normal September, 0.13 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 25°C and low of 15°C, 3 mm of precipitation in September.
- NOAA stationOceanside Municipal Airport
- Station IDUSW00053121
- Location33.22°N 117.35°W
- Elevation28 ft (9 m)
- From the center3 miles
- Population170,941
- Jan 67° 41°
- Feb 66° 42°
- Mar 66° 46°
- Apr 69° 48°
- May 70° 54°
- Jun 73° 58°
- Jul 77° 62°
- Aug 78° 62°
- Sep 78° 59°
- Oct 75° 53°
- Nov 71° 44°
- Dec 66° 40°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Oceanside in September?
The normal high is 78°F and the normal low 59°F, for a daily mean of 68.5°F. September is 1.7°F cooler than August and 4.7°F warmer than October. September is the 3rd warmest month of the year in Oceanside and the 9th wettest. Across the month the normal high falls 3°F, from 79°F on September 1 to 76°F on September 30. From one year to the next September's mean temperature typically moves about 2.5°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 66°F and 71°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 11%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 79°F | 61°F | 3% | 0% |
| September 8 | 79°F | 60°F | 4% | 1% |
| September 15 | 78°F | 60°F | 6% | 1% |
| September 22 | 77°F | 59°F | 8% | 1% |
| September 30 | 76°F | 57°F | 11% | 2% |
Every day of September: normal high, low and chance of precipitation (warmest afternoon September 1, coldest night September 30)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| September 1 | 79°F | 61°F | 3% | 0% | 12 h 50 min |
| September 2 | 79°F | 61°F | 3% | 0% | 12 h 50 min |
| September 3 | 79°F | 61°F | 3% | 0% | 12 h 50 min |
| September 4 | 79°F | 61°F | 3% | 0% | 12 h 50 min |
| September 5 | 79°F | 61°F | 3% | 1% | 12 h 50 min |
| September 6 | 79°F | 60°F | 4% | 1% | 12 h 40 min |
| September 7 | 79°F | 60°F | 4% | 1% | 12 h 40 min |
| September 8 | 79°F | 60°F | 4% | 1% | 12 h 40 min |
| September 9 | 78°F | 60°F | 4% | 1% | 12 h 40 min |
| September 10 | 78°F | 60°F | 4% | 1% | 12 h 40 min |
| September 11 | 78°F | 60°F | 5% | 1% | 12 h 30 min |
| September 12 | 78°F | 60°F | 5% | 1% | 12 h 30 min |
| September 13 | 78°F | 60°F | 5% | 1% | 12 h 30 min |
| September 14 | 78°F | 60°F | 5% | 1% | 12 h 30 min |
| September 15 | 78°F | 60°F | 6% | 1% | 12 h 30 min |
| September 16 | 78°F | 59°F | 6% | 1% | 12 h 20 min |
| September 17 | 78°F | 59°F | 6% | 1% | 12 h 20 min |
| September 18 | 78°F | 59°F | 7% | 1% | 12 h 20 min |
| September 19 | 78°F | 59°F | 7% | 1% | 12 h 20 min |
| September 20 | 78°F | 59°F | 7% | 1% | 12 h 20 min |
| September 21 | 77°F | 59°F | 8% | 1% | 12 h 10 min |
| September 22 | 77°F | 59°F | 8% | 1% | 12 h 10 min |
| September 23 | 77°F | 58°F | 8% | 1% | 12 h 10 min |
| September 24 | 77°F | 58°F | 9% | 1% | 12 h 10 min |
| September 25 | 77°F | 58°F | 9% | 2% | 12 h 10 min |
| September 26 | 77°F | 58°F | 9% | 2% | 12 h |
| September 27 | 77°F | 58°F | 10% | 2% | 12 h |
| September 28 | 77°F | 57°F | 10% | 2% | 12 h |
| September 29 | 77°F | 57°F | 11% | 2% | 12 h |
| September 30 | 76°F | 57°F | 11% | 2% | 11 h 50 min |
- Normal high
- 78°FSeptember average
- Normal low
- 59°FSeptember average
- Precipitation
- 0.13 inmonth total
- Days with precipitation
- 20.01 inch or more
- Days at 90°F or more
- 1
- Daylight
- 12 h 50 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 30
- Days at 80°F or more
- 9
- Sunshine
- 91%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00053121; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Oceanside in September?
On a given September day the chance of 0.01 inch or more is 6% on average, highest around September 30 (11%). In all, 0.13 in falls on 2 days of a normal September.
In a normal September in Oceanside, 1 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00053121.
What are the records for September in Oceanside?
The warmest September temperature on this station's record (since 1999) is 105°F, on September 27, 2010; the coldest is 45°F, on September 28, 2005. The wettest September brought 1.14 in (2015).
The September mean against the 1991-2020 normal of 68.5°F: 2021 69.1°F (+0.6), 2022 72.9°F (+4.4), 2023 69.6°F (+1.1), 2024 70.2°F (+1.7), 2025 70.2°F (+1.7), 2026 72.5°F (+4.0). 6 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 69.1°F | +0.6°F | 0.02 in |
| 2022 | 72.9°F | +4.4°F | 0.40 in |
| 2023 | 69.6°F | +1.1°F | 0.13 in |
| 2024 | 70.2°F | +1.7°F | 0.01 in |
| 2025 | 70.2°F | +1.7°F | 0.13 in |
| 2026 | 72.5°F | +4.0°F | 0.02 in |
Source: records: ACIS, station USW00053121; recent months: ACIS, station USW00053121. Records and recent months use complete months only.
How does September in Oceanside compare across California?
Across the 219 places PlainClimate covers in California, September normal highs run from 64°F in Eureka to 104°F in Brawley; Oceanside's is 78°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- Oceanside in August78°F by day, 62°F at night
- Oceanside in October75°F by day, 53°F at night
- Oceanside through the yearEvery month, frost dates, records and recent years
- California in SeptemberThe statewide normal and the warmest and coolest places
- Brawley: California's warmest Septembernormal high 104°F