The waterspout was snapped several hundred metres off the coast at 6AM! It was caused by fast-moving, rotating air movements that suck up water from the sea's surface. Waterspouts are common in late summer and early autumn because in these periods seawater is sufficiently hot to allow their formation. Waterspouts are only formed when there is a difference in temperature between seawater and upper layers of air.
Several waterspouts occur on the Belgian and Dutch coasts every year, though not all are photographed. They are less powerful than whirlwinds and consequently less dangerous. They also do not last as long. Craft have little to fear, though surfers and occupants of small boats should watch out.