Onset Water Temperature
3°C / 38°F
The measurements for the water temperature in Onset, Massachusetts are provided by the daily satellite readings provided by the NOAA. The temperatures given are the sea surface temperature (SST) which is most relevant to recreational users.
Monthly average water temp
Monthly average max / min water temperatures
The graph below shows the range of monthly Onset water temperature derived from many years of historical sea surface temperature data.
The warmest water temperature is in August with an average around 68.4°F / 20.2°C. The coldest month is February with an average water temperature of 38.1°F / 3.4°C.
7 day tide forecast for Onset
*These tide times are estimates based on the nearest accurate location (Cape Cod Canal, Buzzards Bay Entrance, Massachusetts) and may differ by up to half an hour depending on distance. Please note, the tide times given are not suitable for navigational purposes.