Nissequogue River water temperature
Nissequogue River, Landing Ave at Smithtown, New York · River
The current water temperature at Nissequogue River is 15.6 °C (as of September 21, 2026, source: USGS).
A river can change temperature within hours — snowmelt, rain or power-plant operations show up immediately. That is why the measured value counts here, not an estimate.
Measurement series & statistics
This measurement series includes 175 data points since August 12, 2026.
Lowest recorded value: 14.4 °C on September 8, 2026 · highest value: 27.0 °C on September 4, 2026.
In September, temperatures have ranged between 14.4 °C and 27.0 °C.
The current value is 3.8 °C below the September average of this series.
Nearby waters
Frequently asked questions
Can you swim at Nissequogue River right now?
The current water temperature is 15.6 °C. See live swimming conditions, weather and quality in the BrrChecker app.
How warm is the water at Nissequogue River?
Currently 15.6 °C (updated continuously).
How warm is at Nissequogue River in September?
In September, the water temperature recently averaged 19.4 °C.
