The 2025-26 UK storm season has begun, and this week marks 10 years since the first named storm. We spoke to researchers at the National Centre for Atmospheric Science to explain why storms are named, what causes storms, why the UK is stormy, why past seasons have been different, what to expect for the new season and as the climate continues to warm.

In the UK, a storm is given a name when it has the potential to cause disruption or damage as a result of strong winds, heavy rainfall or snow, leading to amber or red weather warnings being issued. 

In Europe there are three storm naming groups, and each September there is a new alphabetical list of names issued for the upcoming storm season. The UK storm season begins in September and ends in August the following year. 

In Western Europe the list of named storms is created by the Met Office in collaboration with the Irish and Dutch weather services. This coincides with when we expect to experience extreme storms, due to low pressure weather systems that occur in the autumn and winter months. 

Storms can impact many countries at once, and to avoid confusion, the UK adopts a storm name if another European weather service has already named it.

The UK is renowned for being stormy, and it’s because of the jet stream. The jet stream is a core of strong winds around 8-11 km above the Earth’s surface, blowing from west to east, which directs storms across the Atlantic to the UK. 

Storms start with air being forced to move by differences in atmospheric pressure. The Earth’s rotation then makes that wind circulate around areas of lower pressure, known as a cyclone or storm. If there is a greater difference in pressure, this causes stronger winds around the cyclone.

Storms also move moisture around the atmosphere, by creating conditions that make warm and moist air rise. Wherever the warm, moist air rises, clouds are formed. The formation of clouds releases energy that can further intensify the storm. 

As the jet stream moves storms across the Atlantic, they can draw up more and more moisture, and that’s why storms often bring heavy rainfall to the UK. 

In the UK’s 2024-25 storm season there were six named storms. Storm Floris, the last one to hit in early August, was notable for its wind strength during the summer months. Looking back to the beginning of the calendar year, January’s Storm Eowyn was the most powerful windstorm in the UK for over a decade with gusts of over 135mph. 2024-25 was a much quieter storm season than the previous one. 

In 2023-24 there were 12 named storms, which was the most in a season since the naming of storms started in 2015. Storm Henk, which made landfall in the UK on Tuesday 2 January 2024, also marked the quickest arrival of a storm beginning with ‘H’ on record.

El Niño likely had a strong influence on the 2023-24 season of storms, as El Niño conditions typically result in a stormier autumn and early winter, and a shift in the position of the jet stream. 

“The strongest driver of variability is usually El Nino Southern Oscillation, a pattern of sea surface temperature variability in the tropical Pacific. At this stage, the best indication from seasonal forecast models is to expect a weak La Nina signal (cooler than usual tropical Pacific Ocean temperature), which is normally associated with a positive North Atlantic Oscillation (NAO) and more stormy conditions for the UK. 

“On the other hand, the latest ECMWF sub-seasonal forecast actually shows a good chance of a very weak polar vortex and a higher likelihood of a Sudden Stratospheric Warming, which is often followed by weaker storm track activity and cold weather.

“A Sudden Stratospheric Warming would be very uncommon this early in the season, and hasn’t happened in November since 1968. Overall, seasonal models show a preference for a stormier winter, but the weak vortex could offset this in early winter, possibly bringing colder, more settled conditions in December,” sets out Dr Matt Patterson, research fellow at the National Centre for Atmospheric Science and University of St Andrews.

“The Copernicus Climate Change Service emphasises the large uncertainties around the circulation patterns affecting Europe and the UK. For example, the Australian and French seasonal forecast models predict a rather windy (stormy) winter season, whereas the ECMWF and Japanese models say the opposite. Several models, including the one from the UK Met Office, see no clear signal either way,” says Dr Antje Weisheimer, research scientist from the National Centre for Atmospheric Science and University of Oxford.   

“As human-caused climate change continues to warm the atmosphere, the air is able to hold more moisture. This leads to more condensation in clouds, releasing more energy and intensifying storms. The result is that storms with heavy rain are expected to become more common, and storms with strong surface winds may be more damaging. The most damaging UK storms tend to be those which intensify quickly, known as explosively deepening cyclones, and these are particularly sensitive to the availability of moisture to fuel their development.

“But other factors also contribute to the overall storminess of the UK. For example, the large-scale temperature contrast between the sub-tropical and polar air masses, key for storm development, is decreasing as the Arctic rapidly warms. This is expected to contribute to fewer storms overall, even if the most extreme storms intensify. Predicting the contrasting impacts of our changing climate on UK storms remains an important challenge and the subject of ongoing scientific research,” explains Dr Ben Harvey, research scientist at the National Centre for Atmospheric Science and University of Reading.