Why is the UK so rainy this year and how is the climate crisis making matters worse?

It has rained in parts of the country every day of the year so far and downpours are expected to continue this week

In a “miserable and relentlessly wet” start to the year, rain has fallen somewhere in the UK every single day for weeks on end.

With more than 100 flood warnings in force across the country and further downpours forecast this week, scientists say the atmospheric forces behind Britain’s endless drizzle are the same ones driving devastating floods across Spain and Portugal.

How bad is the rain across the UK?

Northern Ireland has recorded its wettest January in 149 years according to the UK Met Office, while southern England has endured its sixth wettest January since records began in 1836. Rainfall in the south-west was 56% above the long‑term average, rising to 88% above average across the south-east and central southern England.

North Wyke in Devon, Cardinham in Cornwall and Astwood Bank in Worcestershire have recorded rain every day so far this year, the Met Office said on Monday.

Jess Neumann, a hydrologist at the University of Reading, said: “It’s been a miserable and relentlessly wet start to the year for many across the UK.” The commuter town near London has had its longest unbroken spell of rainfall since records began more than a century ago.

“It seems hard to remember that only a few months ago, large parts of the UK were experiencing drought and hosepipe bans.”

Why is the UK so rainy?

The seemingly continuous rain has been driven by a rapid-fire succession of weather systems. Storms Goretti, Ingrid and Chandra battered the UK in January, with back-to-back deluges that have pushed soil in parts of the country to saturation point.

Neil Armstrong, a chief forecaster for the Met Office, said: “The past few weeks have felt relentlessly wet, with repeated bands of rain sweeping in from the Atlantic and creating increasingly saturated ground across large parts of the UK.”

The conditions have been fuelled by a southward shift in the jet stream – a conveyor belt of fast-flowing air – steering successive areas of low pressure towards the UK.

“Cold plunges of air across North America have strengthened the temperature gradient across the north-west Atlantic, energising the jet,” Armstrong said. “A blocking high over northern Europe has prevented weather fronts from clearing, causing them to stall over the UK.”

Where have storms struck?

The same shift in the jet stream has also battered Spain and Portugal with devastating floods, killing several people and forcing thousands from their homes. Storm Leonardo, which merged with a rainfall-laden “atmospheric river” carrying tropical moisture from the Caribbean, was followed by Storm Marta at the weekend, which killed two people.

While the low pressure systems in the UK have not intensified as rapidly, they have still been powerful enough to break daily rainfall records in several locations. Scientists warn that even modest rainfall can trigger flooding when soils are already saturated and unable to absorb more water.

Is the climate crisis making rainfall worse?

Scientists think fossil fuel pollution is making the jet stream more erratic, allowing extreme weather systems – from heavy rain to heat domes – to become stuck over the same areas for prolonged periods, amplifying their impacts. These so-called blocking systems are expected to become more frequent under medium- and worst-case emissions scenarios.

At the same time, global heating is intensifying rainfall. Warmer air can hold about 7% more moisture for every 1C rise in temperature, a shift that has contributed to increasingly wet UK winters arriving roughly two decades earlier than regional climate models had predicted. In January, however, Arctic air led to slightly cooler temperatures than usual, with high monthly rainfall totals more a result of persistence and duration than intensity.

Scientists project climate breakdown will bring wetter winters and drier summers to the UK. Neumann said: “One positive to come from the recent rainfall is the move to recovery status for UK water resources.” She added that England is now free from drought for the first time since May, with reservoirs and aquifers slowly restocking and recharging to healthy levels.