An amber weather warning is in force for millions of people, with more than a month’s worth of rain set to fall in some areas today.
The warning for heavy rain came into force at around 8:15am and will remain in place until 9pm, sweeping over Bath, Oxford, Reading and Milton Keynes.
The Met Office originally issued an amber warning covering Worcester, Birmingham, Nottingham and Hull before updating its advice.
Many places could see between 60mm and 80m (2.36in and 3.15in) – with up to 120mm (4.72in) possible in a few locations, according to the Met Office.
Forecasters are warning of potential flooding, difficult driving conditions and delays on public transport – and the chance of outbreaks of lightning.
Power cuts to some homes and businesses are likely and there is a possibility some communities will be cut off by flooded roads, the Met Office said.
A larger but less severe yellow rain warning is also in place until midnight covering the North East, the Midlands, the South East, much of the southern tip of England and eastern Wales.
The amber and yellow warnings in place in the UK. Pic: Met Office
The Met Office said some areas were at particular risk because the land is already sodden from storms in recent days.
It said a month’s-worth of rain fell in some areas on Sunday, with Woburn in Bedfordshire getting 108.8mm (4.29in).
Even before the warnings took effect, Bedfordshire Police said it was aware of “multiple issues” caused by the weather and urged people to only contact them if “there is an immediate threat to life or crime in progress”.
A flooded road in Dagnall, Buckinghamshire
“All emergency services and council teams are working as quickly as possible to help those affected but our priority will be the vulnerable,” it said.
“Please stay clear of flooded roads and affected areas.”
See the Sky News forecast for your area
Drivers faced wet weather on the M3 motorway near Basingstoke on Friday. Pic: PA
Many places have basked in higher than average temperatures over the last few weeks – but that was probably summer’s last hurrah as autumn beds in.
Met Office forecaster Jonathan Vautrey warned below-average temperatures are on the way as northerly winds push in.
“All of us will start to see temperatures dropping below average for the time of year as we head towards the end of the week,” he said.
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As of 9am, 12 flood warnings – meaning flooding is expected – were issued for England by the Environment Agency.
Areas affected by the flood warnings include Atherstone in Warwickshire, Leighton Buzzard and Luton in Bedfordshire and parts of London including Wimbledon and South Ruislip.
Monday’s downpours are forecast to ease overnight into Tuesday, but the rain is set to be persistent for many this week.
“Through Wednesday and Thursday, unsettled weather is set to return as frontal systems move in from the Atlantic, bringing showers or longer spells of rain to many parts of the UK,” said Met Office deputy chief meteorologist David Oliver.
Meanwhile, Sunday also marked the autumnal equinox – when the day and night are the same length.
Astronomers regard it as the start of the season but weather forecasters generally count the season as beginning on 1 September.
