The gales and heavy rain that battered Britain over the weekend will be back on Wednesday after a brief lull.

Trees were uprooted by 100mph winds at the height of the storms and drivers had to be rescued from cars caught in flash floods. In Birmingham four teenage boys, including two brothers, were killed when their car crashed into a wall in the Moseley area of the city as they drove through torrential rain on Saturday. They were Kamal and Hadi Suweef, 15 and 17, Hasni Ali, 16, and Hamza Siraj, 16. The winds brought scaffolding crashing down and boats were battered and blown on to rocks.

A tornado damaged 60 homes in Benfleet, Essex, and in Devon and Cornwall power lines were brought down, leaving 10,000 homes without electricity. The wild weather also forced the cancellation of the fireworks finale to the Lord Mayor’s Parade in London for the first time in more than 20 years.

Temperatures will be higher than normal this week, reaching 15.5C (60F) in some places, but the storm conditions will make enjoying the unseasonably warm weather difficult. More rain is forecast for today. The Environment Agency warned homeowners to be on their guard for flooding today, as scattered showers are expected to hit already saturated ground.

Tidal flooding was not as serious as was feared after Saturday’s wild weather but the Environment Agency estimated that 50 properties had been flooded by rising surface water.

Nigel Bolton, a forecaster with the Met Office, said: “The weather is going to be very unsettled this week. Monday and Tuesday will have sunny spells and it will be mild in some places but it does go downhill quite significantly after that, with the problem being the rain rather than the wind.

“There will be persistent and heavy rain across the country, particularly in the West and we could get 50-75mm of rain in places falling on already very wet ground. This will continue into Friday, and next weekend looks very unsettled with further rain.”

The agency has seven flood warnings and 47 watches in force and its helpline had nearly 5,000 calls on Sunday. A spokeswoman said: “We are continuing to closely monitor rivers and sea levels and our officers are out on the ground checking flood defences and clearing trash screens.

“A lot of ground is waterlogged and rivers recharged, and with more rain forecast for next week we urge people to remain vigilant. People can check the latest flooding situation on the Environment Agency website and sign up to our free flood warnings service at www.environment-agency.gov.uk or by calling 08459 881188.”