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On this day in 2020... Storm Dennis arrives in the UK

09:00
15 February 2023

On this day in 2020...
Storm Dennis arrives in the UK

Large wavesLarge crashing waves at the harbour of Porthcawl, Wales preceded the arrival of Storm Dennis in 2020. - © 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 from Storm Ciara.

Amid the two days the storm lasted over land, 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 millimetres of rain was recorded in a day, greater than their monthly rainfall average.

A separate station in Aberdaron also recorded wind gusts as strong as 91 miles per hour while 50 miles per hour 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 11, 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 17, Dennis had moved on from the UK and impacted Europe before dissipating a day later.

Ryan Hathaway
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