San Diego in September
Find out everything about the water temperature in San Diego in September. Average, minimum and maximum recorded temperatures as well as daily temperature in September for the last two years. Compare the current month's sea temperature data with other months of the year.
Water temperature in September
Minimum:
63.6 °F
Average:
69.4 °F
Maximum:
75.2 °F
Sea water temperature in San Diego in September
In the city of San Diego, the month of September is somewhat comfortable for swimming. The minimum recorded temperature during this month was 63.6°F on September 20, 2021, with an average temperature being 69.4°F and a maximum temperature reaching 75.2°F on September 14, 2015.
| Date | 10 years average | 2024 | 2023 |
|---|---|---|---|
| Sep 1 | 69.9°F | 70.4°F | 66.2°F |
| Sep 2 | 69.9°F | 69.5°F | 67.0°F |
| Sep 3 | 70.2°F | 70.2°F | 68.3°F |
| Sep 4 | 70.7°F | 70.0°F | 69.4°F |
| Sep 5 | 70.7°F | 70.8°F | 69.4°F |
| Sep 6 | 70.4°F | 70.3°F | 68.8°F |
| Sep 7 | 70.6°F | 70.8°F | 69.6°F |
| Sep 8 | 70.6°F | 71.6°F | 70.1°F |
| Sep 9 | 70.6°F | 71.3°F | 69.9°F |
| Sep 10 | 70.6°F | 71.7°F | 69.8°F |
| Sep 11 | 70.6°F | 71.9°F | 70.0°F |
| Sep 12 | 70.3°F | 71.3°F | 69.7°F |
| Sep 13 | 70.0°F | 70.9°F | 68.8°F |
| Sep 14 | 69.7°F | 71.1°F | 68.3°F |
| Sep 15 | 69.6°F | 70.8°F | 68.2°F |
| Sep 16 | 69.6°F | 70.2°F | 68.1°F |
| Sep 17 | 69.5°F | 69.4°F | 68.0°F |
| Sep 18 | 69.2°F | 68.7°F | 67.8°F |
| Sep 19 | 68.9°F | 68.9°F | 67.3°F |
| Sep 20 | 68.6°F | 68.4°F | 66.9°F |
| Sep 21 | 68.7°F | 68.1°F | 66.5°F |
| Sep 22 | 68.8°F | 68.1°F | 66.2°F |
| Sep 23 | 68.6°F | 67.6°F | 66.1°F |
| Sep 24 | 68.3°F | 68.0°F | 64.8°F |
| Sep 25 | 68.1°F | 67.9°F | 64.2°F |
| Sep 26 | 67.9°F | 66.8°F | 63.8°F |
| Sep 27 | 68.1°F | 65.7°F | 64.0°F |
| Sep 28 | 67.9°F | 65.4°F | 64.2°F |
| Sep 29 | 68.0°F | 65.2°F | 65.9°F |
| Sep 30 | 68.1°F | 64.7°F | 66.9°F |
In an average year, San Diego offers no days when the water temperature is warm enough to swim comfortably.
The warmest water in San Diego was recorded on August 7, 2018, reaching a 75.8°F. While the coldest temperature occurred on February 25, 2023, dipping to 55.9°F. The average readings by season are 60.0°F in Winter, 61.8°F in Spring, 68.6°F in Summer, and 66.7°F in Autumn.
September's average temperature is a slight drop from August's average of 70.4°F. In October, the temperature is expected to decrease further, potentially averaging around 67.1°F.
Popular neighboring cities and resorts
| City | Water temperature* | Distance** |
|---|---|---|
| Tijuana |
56.6°F
|
17mi |
| Oceanside |
60.4°F
|
35mi |
| Laguna Beach |
59.8°F
|
67mi |
* current water temperature in this city
** straight line distance from San Diego