Home / Editor's Pick /

On this day in 2020: Storm Dennis hit the UK and Ireland

10:00
15 February 2024

On this day in 2020
Storm Dennis hit the UK and Ireland

Large wavesLarge crashing waves at the harbour of Porthcawl, Wales provided spectacular sights for locals, but preceded the full arrival of Storm Dennis which devastated the UK. - © picture alliance

On this day in 2020, Storm Dennis impacted the UK and Ireland, becoming one of the most damaging in years building upon the destruction brought a week prior by Storm Ciara.

Amid the two days the storm lasted over land on February 15th and 16th, Dennis delivered heavy rains and strong winds resulting in flooding across the entirety of the UK.

At the River Taff and Rhondda catchments in Wales, more than 160 mm of rain was recorded in a day, greater than their monthly rainfall average.

A weather station in Aberdaron also recorded wind gusts as strong as 91 mph, while 50 mph gusts were also recorded in Kent.

Major incidents were declared across England while south Wales experienced devastating flooding. At Dennis' peak 152 flood warnings were in effect across Wales, the highest number ever in force at one time.

River levels also rose to record highs with the River Taff at Pontypridd reaching its highest level for over 40 years, 80 cm higher than the historic flooding of 1979.

In total seven lives were known to have been lost as a result of Storm Dennis, with five in the UK.

Ireland largely avoided widespread damage from flooding, instead experiencing fierce gale-force winds leading to widespread power outages.

Dennis was named on February 11th 2020, while still situated over southern America. As the storm moved over the Atlantic it experienced explosive intensification becoming one of the most intense extratropical cyclones on record.

By February 17th, Dennis had moved on from the UK and impacted Europe before dissipating a day later.

Weather & Radar editorial team
More on the topic
Shooting stars, part of the Geminid meteor shower.
Saturday, 13 December 2025

Spot a shooting star

King of meteor showers at its peak
People walk through muddy streets after heavy rain, alongside a rain map of Morocco.
Tuesday, 16 December 2025

New rainfall in sight

Fatalities in Moroccan floods
Weather radar showing clouds and showers over Algeria and Morocco. Next to it, a warning map with the rain area in Algeria marked. Surrounding regions mostly sunny and dry.
Thursday, 18 December 2025

Algeria affected

Rain in the desert
All weather news
This might also interest you
Weather map of the UK and Ireland showing scattered showers with cloudy patches across much of the region, especially around western and northern areas. Sunshine symbols appear over London, Cardiff, and parts of southern England, while temperatures range from 17°C to 18°C in most places. Areas of heavier rain are visible over the Atlantic to the west.
Friday, 29 August 2025

Breakfast brief

Unsettled conditions into the weekend
plit image showing a double rainbow over a rocky shoreline on the left and sheep grazing in a green field under stormy clouds on the right.
Sunday, 2 November 2025

Your weather - Your shots

Mixed conditions on an unsettled week
Split weather map showing the UK and Ireland. The left side illustrates strong winds circulating around a low-pressure system, with gusts of 20–30 mph highlighted in orange and yellow. The right side shows radar imagery with widespread blue rain bands and patches of thunderstorms, especially over northern England and Scotland.
Thursday, 28 August 2025

Breakfast brief

Remaining widely unsettled
All articles
Weather & Radar

Weather & Radar is also available on

Google Play StoreApp Store

Company

Contact us Privacy Policy Legal info Accessibility statement

Services

Uploader

Socials

facebooktwittertikToklinkList