South San Francisco Bay water temperature
South San Francisco Bay, Dumbarton Bridge, California · Sea/Coast
The current water temperature at South San Francisco Bay is 20.0 °C (as of September 21, 2026, source: USGS).
The sea lags the air by weeks: the warmest water often arrives after the warmest days. Measured buoy values show this honestly.
Measurement series & statistics
This measurement series includes 384 data points since July 23, 2026.
Lowest recorded value: 19.9 °C on September 21, 2026 · highest value: 23.5 °C on August 14, 2026.
In September, temperatures have ranged between 19.9 °C and 22.7 °C.
The current value is 1.1 °C below the September average of this series.
Nearby waters
Frequently asked questions
Can you swim at South San Francisco Bay right now?
The current water temperature is 20.0 °C. See live swimming conditions, weather and quality in the BrrChecker app.
How warm is the water at South San Francisco Bay?
Currently 20.0 °C (updated continuously).
How warm is at South San Francisco Bay in September?
In September, the water temperature recently averaged 21.1 °C.
When is the water warmest at South San Francisco Bay?
Across the measurement record, August is on average the warmest month (22.3 °C).
