Connecticut River water temperature
Connecticut River, Old Lyme, Connecticut · Sea/Coast
The current water temperature at Connecticut River is 21.5 °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 100 data points since August 26, 2026.
Lowest recorded value: 21.4 °C on September 21, 2026 · highest value: 25.7 °C on August 26, 2026.
In September, temperatures have ranged between 21.4 °C and 24.5 °C.
The current value is 1.6 °C below the September average of this series.
Nearby waters
More measuring points: Connecticut River
Frequently asked questions
Can you swim at Connecticut River right now?
The current water temperature is 21.5 °C. See live swimming conditions, weather and quality in the BrrChecker app.
How warm is the water at Connecticut River?
Currently 21.5 °C (updated continuously).
How warm is at Connecticut River in September?
In September, the water temperature recently averaged 23.1 °C.
