A weather phenomenon known as a sting jet similar to the one seen during the Great Storm of 1987 could form on Friday as Storm Eunice takes hold, scientists have warned.
The Met Office has warned that the weather phenomenon could cause “significant damage and risk to life”.
But what is a sting jet? Matt Priestley, a research scientist at the University of Exeter looking at storm tracks and extratropical cyclones, said they were small areas of very intense winds within a storm’s cyclone that were hard to predict.
“They’re generally about 10 to 20 kilometres wide and are generated by specific instabilities within the flight lines of storms and cause very high wind speeds.
“They’re not a feature of all storms. They’re often just a feature of the most intense ones like Storm Eunice. The fact that they are such small scale but can have such high wind speeds makes forecasting them very, very difficult.”
The Great Storm of 1987, which claimed 18 lives, was the most famous example of a sting jet forming, Priestley said.
“That storm had a sting jet and it uprooted millions of trees. Sting jets cause a big intensity increase compared to the rest of the cycle so they can cause a lot of extra damage very quickly like they did in 1987.”
Sting jets can cause a phenomenon whereby a narrow area of land is hit by very intense winds, which could reach 100mph or more, but 30 miles away there may be much slower wind speeds associated with a normal storm, of about 60-70mph. This means the damage from a sting jet can be very localised.
They usually only last for about three or four hours, whereas the main storm may last a lot longer.
Storm Eunice looks as if it has the features that could create a sting jet. Priestley said: “There has not been a storm this intense for 10 or 15 years.”
The jets get their name from their resemblance to the sting in a scorpion’s tail, the Met Office said. They can be spotted as they develop on satellite images, where the end of the so-called cold conveyor is marked by a hook-shaped cloud with a point at the end.
Dr Peter Inness, a meteorologist at the University of Reading, said a strong jet stream could “act like a production line for storms, generating a new storm every day or two”.
He added: “Eunice looks like it may be able to produce a sting jet, a narrow, focused region of extremely strong winds embedded within the larger area of strong winds and lasting just a few hours.”
He said two red warnings for wind in a single winter was unusual for the UK, as it was more typical to get one every two or three years.
