The UK Met Office has issued two red weather warnings in as many months for strong winds. These are the highest threat levels meteorologists can announce, and are the first wind-only red warnings to be issued since 2016’s Storm Gertrude.

So what’s behind the UK’s recent spate of dangerous wind storms? And are these events likely to become more common in future?

Storm Arwen in late November 2021 caused devastation across Scotland, northern England and parts of Wales. Winds of 100mph killed three people, ripped up trees, and left 9,000 people without power for over a week in freezing temperatures.

The destruction caused by Arwen is still apparent in some areas, and the clean-up from Storm Dudley – which battered eastern England on Wednesday February 16 – is underway at the time of writing.

Now the UK faces Storm Eunice, and its gusts of up to 122 miles per hour. Eunice bears a striking similarity to the “Great Storm” of 1987, which unleashed hurricane-force winds and claimed 22 lives across Britain and France in October of that year.

Both are predicted to contain a “sting jet”: a small, narrow airstream that can form inside a storm and produce intense winds over an area smaller than 100 km.

Storm Eunice: 9 dead, 436 flights cancelled as winds up to nearly 200 kmph ravage across Europe

Sting jets, which were first discovered in 2003, and likely occurred during the Great Storm and Storm Arwen, can last anywhere between one and 12 hours. They are difficult to forecast and relatively rare, but make storms more dangerous.

Sting jets occur in a certain type of extratropical cyclone – a rotating wind system that forms outside of the tropics.

These airstreams form around 5km above the Earth’s surface then descend on the southwest side of a cyclone, close to its centre, accelerating as they do and bringing fast-moving air from high in the atmosphere with them.

When they form, they can produce much higher wind speeds on the ground than might otherwise be forecast by studying pressure gradients in the storm’s core alone.

Meteorologists are still working to understand sting jets, but they are likely to have a significant influence on the UK’s weather in a warming climate.

In 1987, the models used for weather forecasts were incapable of representing sting jets, but improvements mean that forecasters predicted Storm Eunice before it had even begun to form in the Atlantic.

Over the past decade, our team at Newcastle University has worked closely with colleagues at the UK Met Office to develop new high-resolution climate models that can simulate sting jets, as well as hail and lightning, to illuminate how extreme weather events might change in a warming climate.

We already know that, as the world warms, downpours are intensifying. The simple reason is that warmer air can hold more moisture. The UK saw the wettest day on record in 2020, already estimated to be 2.5 times more likely because of greenhouse gas emissions.

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