Why are there so many storms and are they getting worse? Met Office confirms Jocelyn after Isha disruption

A fallen tree in floodwater in York. Storms are set to increase in number (Danny Lawson / PA)
A fallen tree in floodwater in York. Storms are set to increase in number (Danny Lawson / PA)

Storm Jocelyn has wreaked havoc across parts of the UK this week, with 97mph gusts of wind causing severe travel disruption.

Just days after Storm Isha, a fresh wave of bad weather swept in with Storm Jocelyn, marking the 10th named storm of the season.

In the latest round of travel misery, the Queen Elizabeth II bridge at the Dartford Crossing was forced to shut as a result of severe wind.

Thousands of homes also remained without power on Wednesday amid a slew of yellow and amber weather warnings.

While the worst of Jocelyn might be over for the country, with weather conditions easing, it feels like the UK hasn’t been able to catch a break recently.

Back-to-back storms this week aren’t just bad for travel, but it’s also a sign of shifting weather conditions, climate change, and environmental events.

At this point, it remains to be seen whether the UK will continue to experience more severe weather – but the climate experts seem to think that’s probably the case.

Storm names chosen by the Met Office (Met Office)
Storm names chosen by the Met Office (Met Office)

How and why are storms named?

The Met Office names storms to raise awareness that bad weather is on the way.

Alex Drakin, of the agency, said: “We only name storms when it is especially lively and potentially damaging and disruptive. Word gets spread wider… people are more likely to change their plans and take action.”

The Met Office has been naming storms for eight years and the practice is now so popular that it even has a ‘name reveal’ on its YouTube channel.

Met Éireann in Ireland and KNMI in the Netherlands are part of a group with the Met Office and all three contribute to naming the storms.

Other European countries are also in other leagues with their naming of storms. Sometimes names can transfer when storms blow around the continent.

New names are picked every September for the year to come. It is likely that the Met Office will not need to get through all 26 letters – but the growing number of storms means we might progress through the alphabet a lot quicker.

How many storms have there been this year?

The first storm in the 2023/24 season was Storm Agnes, which hit on September 27-28.

Isha was the ninth storm of the year, closely followed by Jocelyn, which was the tenth.

The Met Office named storms for 2023/24 (Met Office)
The Met Office named storms for 2023/24 (Met Office)

All names that did not feature (Storm Wouter, for example, in 2022-23) are wiped and will not be used.

Have storms been getting worse?

In 2015-16, there were a record number of storms as the alphabet got down to K – but it is likely that record will be broken, as we are already at J.

How often we have storms depends on weather phenomena.

There were far fewer storms in the 2022-23 season, with the naming only getting as far as B on the list. This was partly down to the jet stream being weaker than usual during that period.

In February 2022 (in the 2021-22 season), there were three named storms in one week due to a more powerful than average jet stream across the Atlantic.

However, the bigger picture shows that human-caused climate change could bring about more regular storms.

Tree surgeons remove a fallen tree from cars during Storm Isha in Linlithgow (Lesley Martin / Reuters)
Tree surgeons remove a fallen tree from cars during Storm Isha in Linlithgow (Lesley Martin / Reuters)

A warmer atmosphere could lead to greater rainfall, more frequently.

The National Centre for Atmospheric Science writes: “The extra release of energy by clouds will likely lead to an increased rate of storms that rapidly intensify and a strengthening of the most extreme storms.

“But while a warmer world is likely making the most extreme storms more intense, the change in the overall number of storms is more uncertain and remains a subject of ongoing scientific research.”

The centre added that currently one third of all storms with strong surface winds, and nearly half by the end of the century, in the North Atlantic region may be accompanied by powerful sting jets as a result of global warming.

What are sting jets?

These are narrow jets of air that accelerate as they descend. They can cause extremely strong and damaging surface winds in a relatively small area of the storm.

Storm Eunice, which hit the UK in February 2022, was associated with a sting jet.

Dr Ambrogio Volonté, of the National Centre for Atmospheric Science, said: “They are called sting jets as they descend from the tip of the hooked cloud that gradually wraps around the area of low pressure at the centre of the storm.

“The presence of a sting jet can make intense storms, with strong surface winds, even more damaging.”