Home / Editor's Pick /

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

17:00
15 February 2025

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. - © picture alliance

On this day in 2020, Storm Dennis impacted the UK and Ireland, becoming one of the most damaging weather events in years.

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, just weeks after Storm Ciara.

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.

Ryan Hathaway
More on the topic
Weather map of the UK and Ireland showing orange-red wind zones with gusts up to 40 mph near Dublin and Glasgow, overlaid with a triangular wind warning symbol on the left.
Friday 14 November 2025

Turbulent Saturday

Gusting start to the weekend
Weather map with heavy rain warning over Southern California, warning symbol in the centre.
Saturday 15 November 2025

Severe weather conditions

Heavy rainfall in California
Temperature map of Europe showing wintry conditions in the north-east, and summer warmth in the south-east.
Friday 21 November 2025

Winter meets summer

Large temperature contrasts in Europe
All weather news
This might also interest you
Sunday 17 August 2025

Your weather - Your shots

Summer shots from a warm week
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
Split weather map showing UK wind speeds in orange-red shades up to 40 mph on the left and warning levels in green-yellow on the right, with a central wind warning sign.
Wednesday 22 October 2025

Warnings active

Storm Benjamin impacts the UK
All articles
Weather & Radar

Weather & Radar

Google Play StoreApp Store

Company

Contact us Privacy Policy Legal info Accessibility statement

Services

Uploader

Socials

facebooktwitteryouTubelinkList