BBC Wales meteorologist Derek Brockway said the wind and rain caused temperatures to plummet to one of the coldest early May Bank Holidays on record.
He wrote on Twitter at 3.30pm yesterday: “The wind has reached storm force 10 on Mumbles Head in Swansea with a gust of 74mph this afternoon.
“As well as being wet, it’s also one of the coldest early May bank holidays on record.
“Temperatures in most places in single figures.”
The stormy conditions left homes without power for hours on end, as the wind and heavy rain battered the region.
Both Western Power Distribution and Scottish Power Energy Networks suffered power outages.
The worst affected regions were in Conwy, Gwynedd and Anglesey.
Dozens of major roads were also forced to closed, due to flooding and uprooted trees.
Traffics cops reported a number of incidents on major roads such as the A34 Northbound, the M4 Westbound and the M3 last night.
Power cuts were also recorded in areas of the county, including West Berkshire.
This morning, power outages were reported in Padworth.
A yellow Met Office wind warning remains in force until 9am, which covers huge swathes of southern England and Wales.
The heavy downpours seen in Monday are also expected to continue through the morning.
A Met Office forecaster said: “As we head into Tuesday we will see the heavy, persistent rain clearing to the east but showers are following behind and it is going to remain windy.”
BBC forecasters added: “Today, scattered showers will persist through the day, wintry over the Scottish hills.
“Showers will be most frequent in central areas, with sunny spells developing further north and south. Breezy.”