Seeing a waterspout is always impressive, but sometimes it happens in groups. Some lucky people have been able to observe up to five or even ten waterspouts simultaneously on certain coasts.
Waterspouts are whirlpools similar to tornadoes, but they just don’t happen in the same place: tornadoes happen on land, and waterspouts happen at sea or on a lake. In addition to being often much weaker than tornadoes, waterspouts also have another difference with tornadoes: they regularly occur in several groups, they are then called “multiple waterspouts” or “waterspout families”. marines”. Their number can vary from 2, to 3, sometimes 5 or 6, and even up to more than 10 simultaneous waterspouts! These waterspouts occurring at the same time are not uniform, with some being much larger than others.
Multiple waterspouts sometimes form in good weather
Like tornadoes, most waterspouts form under a thunderstorm. In this case, it is the most common “tornadic waterspouts”. They form under the most violent thunderstorms, the supercells, due to the instability and wind shear associated with the currents generated by the cumulonimbus.
Multiple waterspouts can also form in calm weather, under a single cumulus, ‘fair weather waterspouts’ or ‘cold air waterspouts’. In tropical regions, the phenomenon is even quite common in summer, often early in the morning or late in the evening. All it takes is a large difference between water temperature and air temperature, combined with winds from different directions meeting, as in the case of Dust Devils (dust devils) on earth.
Some of these winds are sometimes from a thunderstorm that circulates nearby, but not directly in the area. These winds converge and rise, creating a small vortex that rolls up and cumulus clouds: the result is cumulus clouds associated with fair weather, under which is one or more waterspouts. The presence of families of waterspouts is very common in this case, because the winds converge on a meeting line which can spread over tens or hundreds of meters, with many cumulus clouds and therefore sometimes 5 or 10 waterspouts more or less aligned!
This type of formation would explain why multiple waterspouts are much more common than multiple tornadoes which are much rarer. The sighting of twin tornadoes, consisting only of two whirlpools, is an exceptional phenomenon, while the appearance of multiple waterspouts are frequent each summer and autumn.
Four simultaneous waterspouts in Thailand in 2018. © Cycloneoi
The best places in the world to spot multiple waterspouts
All the coasts of the world are capable of hosting waterspouts when the weather conditions are met. But there are hotspots waterspouts around the world, including the Mediterranean coasts of France and elsewhere. The surroundings of Nice and Bastia are among the best areas to see waterspouts, which are sometimes powerful and impressive. But, as far as multiple waterspouts are concerned, you have to go even further south, towards Italy, Croatia, Greece, and Majorca.
In the United States, the hot and humid coasts of the Gulf of Mexico are also among the best spots to see, several times a year, and even during the summer several times a month, entire families of waterspouts: Florida (in the Keys archipelago) and Alabama in particular, but also South Carolina.
The Great Lakes of the United States, such as Lake Michigan, are sometimes also the scene of multiple waterspouts, as are Cuba, Thailand, and closer to home, the Netherlands and Finland.