Portstewart Sea Temperature
5°C / 42°F
The measurements for the water temperature in Portstewart, N Ireland 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 Portstewart water temperature derived from many years of historical sea surface temperature data.
The warmest water temperature is in August with an average around 57.6°F / 14.2°C. The coldest month is March with an average water temperature of 46.8°F / 8.2°C.
7 day tide forecast for Portstewart
*These tide times are estimates based on the nearest accurate location (Portrush, Northern Ireland) and may differ by up to half an hour depending on distance. Please note, the tide times given are not suitable for navigational purposes.