Connecticut River at Old Lyme, Connecticut · Sea/Coast
The current water temperature at Connecticut River at Old Lyme is 22.1 °C (as of September 20, 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.
This measurement series includes 113 data points since August 26, 2026.
Lowest recorded value: 21.5 °C on September 2, 2026 · highest value: 25.7 °C on August 26, 2026.
In September, temperatures have ranged between 21.5 °C and 24.5 °C.
The current value is 1.0 °C below the September average of this series.
Can you swim at Connecticut River at Old Lyme right now?
The current water temperature is 22.1 °C. See live swimming conditions, weather and quality in the BrrChecker app.
How warm is the water at Connecticut River at Old Lyme?
Currently 22.1 °C (updated continuously).
How warm is at Connecticut River at Old Lyme in September?
In September, the water temperature recently averaged 23.1 °C.