Torrential downpours are set to bring “dangerous” flooding across the UK this week, forecasters have warned.
The Met Office said large waves, heavy rain, strong gales and potential river flooding will affect the west coast of England, much of Wales and parts of Scotland from Thursday.
A yellow rain warning has been put in place in these areas and will last until Sunday evening.
The weather could cause damage to homes and businesses, travel cancellations and power cuts, forecasters said.
Most of the UK is to experience mild, average October temperatures during this period.
But up to 150mm of rain could fall in the mountainous regions of Wales and Cumbria within two days.
Met Office forecaster Marco Petagna said: “On Thursday and Friday, a band of low pressure will start to sweep in from the north-west, and will affect areas from Cornwall to Northern Ireland.
“There is likely to be incredibly heavy wind and rain in these regions, with gales of 50-60mph in exposed areas, perhaps leading to waves of around 10-11m.
“Around 40mm of rain could fall each day in some parts”.
On Wednesday, waves brought on by Hurricane Epsilon are believed to have reached near historic highs of between 10 and 15 metres in Mullaghmore, Co Sligo, Ireland.
It comes as forecasters said Londoners could experience the wettest month for more than 150 years.
The capital has had 139mm of rain up to the 25th, compared with the full month’s average of 78mm.
October 2020 is already the ninth rainiest month in London since 1862.
Mr Petagna said: “It could be the case that the next few days of rain could make this one of the wettest October’s London has had.”
Britons have also been warned of life-threatening floods set to impact certain regions over the weekend, as more rain falls on the already saturated ground.
The “unusual amount” of rain is the result of low pressure moving in from across Atlantic.
Mr Petagna added: “People should be very careful over the weekend, more rain will fall, increasing the chance of river and road flooding.
“Weather like this can be very dangerous and can pose a risk to those out and about, especially on the roads.”