The Flood Forecasting Centre is warning of a deluge in south-east England, where a month’s worth of rain is expected in the next two days.

Four flood alerts have been issued across England, and the Met Office issued an amber “be prepared” warning for heavy rain in London and the south due to intense thundery downpours, with likely travel disruption and a potential risk to life and property.

The Environment Agency’s executive director of flood risk management, John Curtin, warned there could be “issues all week” as the heaviest downpours were still to come. The overall flood risk has been set at “medium”.

The Flood Forecasting Centre, run by the agency and the Met Office, said significant river floods were possible and the four alerts remained in place on Monday evening: by the River Cole and Dorcan Brook; in the Middle Exe area in the south-west; around the River Wandle in south London; and also across the London boroughs of Lewisham, Bromley, Greenwich and Croydon along the River Ravensbourne.

On Tuesday, the heaviest rain is expected to be seen across the east of England, with 60mm of rain forecast in some places, though it will be “a wet day” for many parts of the UK, according to Alex Burkill, a meteorologist at the Met Office.

“The rain will continue through Wednesday to Thursday, with up to 100mm in some high ground spots in eastern England and into northern Wales,” he said. “We’re in for a very wet spell. These sorts of spells are not unheard of, but it’ll be a very wet one, and it will last for a few days. That’s why we’re likely to see impacts such as flooding and travel disruption.”

He added that June is usually the third driest month of the year, but the current weather stood in contrast to June 2018 where many stations saw less than 2mm in a month. The England average for June rainfall is about 62mm for the month.

“It really is a very wet period that we’re entering. This is quite exceptional at this time of year.”

The Met Office has also issued yellow “be aware” warnings for rain in south-east England, East Anglia and the east Midlands from 4pm on Monday, as well as three more warnings for rain from Tuesday to Thursday in the east Midlands, east Yorkshire and the north-east.

The latest radar shows many areas are now seeing heavy #rain, with a line of thunderstorms pushing into Kent and East Sussex #WeatherAware pic.twitter.com/RwNxzo0Gsg — Met Office (@metoffice) June 10, 2019

Fast flowing flood water “causing danger to life”, power cuts and thunderstorms are also possible, forecasters added.

“Homes and businesses are likely to be flooded, causing damage to some buildings,” the Met Office said. “Delays and some cancellations to train and bus services are likely with spray and flooding probably leading to difficult driving conditions and some road closures.”

Forecasters said the northern home counties, the east Midlands, Lincolnshire and the Humber could have some of the heaviest and most persistent rain later in the week.