The increase in sea water height from the level that would normally occur were there no storm. Although the most dramatic surges are associated with hurricanes, even smaller low pressure systems can cause a slight increase in the sea level if the wind and fetch is just right. It is estimated by subtracting the normal astronomic tide from the observed storm tide.
SURGE
Meaning of SURGE in English
Weather and meteorology English vocabulary. Английский словарь погоды и метеорологии . 2012