Water being a liquid, it can easily be made to change shape by exerting a pressure at a point. Just fill a balloon with water and knead it with your fingers. Water in the oceans is constantly subject to changing pressures. When the wind blows, waves are formed. When the weather is fine, typically we have high atmospheric pressures and when the weather is bad, typically we have low atmospheric pressures. These high and low pressures act like the kneading of our fingers on the water filled balloon. Water is pushed from areas of high pressure to areas of low pressure. This means that bad weather is often accompanied by higher sea levels, and much higher sea levels during a high tide. If the tide is a spring tide, where the tides and anyway higher because of the Earth-Moon-Sun alignment, disastrous flooding mat occur.
Precisely this combination occurred between 31 January and 1 February 1953 in the North Sea. The Netherlands, Belgium and the UK were affected. a total of 2,551 were killed and 9% of total Dutch farmland was flooded, 30,000 animals drowned, and 47,300 buildings damaged of which 10,000 destroyed.
