BrrChecker

San Francisco Bay water temperature

San Francisco Bay, China Camp · Sea/Coast

The current water temperature at San Francisco Bay is 19.3 °C (as of September 20, 2026, source: NOAA NERRS SWMP).

The sea lags the air by weeks: the warmest water often arrives after the warmest days. Measured buoy values show this honestly.

19.3 °C
Measured: September 20, 2026 · continuously updated
💧 Water 19.3° · ☀️ Air 13.8° · high today 23.6°
Temperature trend of recent weeks

Water quality

Official EPA rating: excellent

Measurement series & statistics

This measurement series includes 69 data points since September 1, 2026.

Lowest recorded value: 17.9 °C on September 7, 2026 · highest value: 22.6 °C on September 9, 2026.

In September, temperatures have ranged between 17.9 °C and 22.6 °C.

The current value is 0.4 °C below the September average of this series.

Nearby waters

More measuring points: San Francisco Bay

Frequently asked questions

Can you swim at San Francisco Bay right now?
The current water temperature is 19.3 °C. See live swimming conditions, weather and quality in the BrrChecker app.

How warm is the water at San Francisco Bay?
Currently 19.3 °C (updated continuously).

How warm is at San Francisco Bay in September?
In September, the water temperature recently averaged 19.7 °C.

How is the water quality at San Francisco Bay?
The official classification is: excellent.

Open in the BrrChecker app

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