In the UK, we’re accustomed to various weather events like rain, hail, sleet, snow and more - however, tornados aren’t something that we would expect to see outside our windows.
But that’s exactly what was seen over the weekend - an extremely rare weather phenomenon known as a ‘waterspout’. Spotted in the Bristol Channel, near Portishead, at 4pm on Sunday 16 August, the weather event was witnessed by weather watchers who posted a video on social media.
Talking to Bristol Live, BBC Points West weatherman Ian Fergusson (a fellow of the Royal Meteorological Society) said, “It’s an impressive sight. I’ve seen a handful reported over that area in the past decade and this is certainly one of the most spectacular.”
What is a waterspout and how do they form?
National Ocean Service (NOS) explains that waterspouts fall into one of two categories - either fair weather waterspouts or tornadic waterspouts.
Tornadic waterspouts are tornadoes that form over water, or that move from land to water.
“They have the same characteristics as a land tornado,” NOS states.
“They are associated with severe thunderstorms, and are often accompanied by high winds and seas, large hail, and frequent dangerous lightning.”
Fair weather waterspouts, on the other hand, are not generally associated with thunderstorms.
Instead, they form along the dark, flat base of a line of developing cumulus clouds. By the time the funnel of a fair weather waterspout is visible, the waterspout itself is near maturity. Fair weather waterspouts form in light wind conditions, so generally move very little.
National Geographic says, “Both tornadic and fair weather waterspouts require high levels of humidity and a relatively warm water temperature compared to the overlying air.
“Waterspouts are most common in tropical and subtropical waters, such as the Florida Keys, the islands of Greece, and off the east coast of Australia.”
Are waterspouts dangerous?
Waterspouts can put swimmers and boaters at risk, as well as posing a threat to aircraft.
Helicopters flying near waterspouts can be damaged and thrown off course due to the intense winds.
They have been described as “just as dangerous as a tornado” if you get close to one in a boat.
NOS says, “If a waterspout moves onshore, the National Weather Service issues a tornado warning, as some of them can cause significant damage and injuries to people.”