The storm clouds are gathering over Britain. Not because the future of the country hangs in the balance as people go to the polls – the storm clouds are actually gathering.

Some have already gathered and done their worst. Over east London on Wednesday evening, lightning crackled through the night sky and a deluge left some streets momentarily flooded. Barking and Lewisham reported streets under water.

Red “immediate action” flood warnings were issued for parts of south-east London and Essex as parts of the capital saw a month’s rain fall in a matter of hours.

London Fire Brigade (LFB) said it received hundreds of calls to reports including lightning striking property, flooded homes and businesses and rising waters trapping vehicles.

An LFB spokesman said: “Between around 1.30am and 3am our control officers took over 300 calls – around as many as they would receive in an average day.”

Commuters were greeted with the prospect of rain and, more immediately, a deluge of delays on rail lines.

Tube lines affected included Central, Circle, District, Hammersmith & City and Metropolitan which were affected by a combination of signal failures and flooding in outer stretches.

Canning Town station was closed to both DLR and Jubilee customers.

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The London Overground was part suspended because of a fault train at Hackney Wick and there was no service between Liverpool Street and Ilford due to flooding. The DLR was also briefly suspended.

The deluge on Wednesday evening has left its mark on suburban routes too with delays and cancellations on some routes to London from the south east, including areas around Blackheath.

Abellio Greater Anglia, South West Trains and Southern have all warned of major delays on some routes.

Wandsworth Common under water

A Network Rail spokesman said: “It’s a very fast moving picture this morning, with flash floods still arising and others falling in a variety of different routes into London.

“In addition, we are dealing with the aftermath of lightning strikes at Surbiton, which is on the main line into Waterloo, and at Blackheath.

“Our advice to passengers in the South East this morning is to please check before you travel, either with your operator’s website or on National Rail Enquiries.

“Our staff have been out all night and are still out in the rain working with pumps and repairing damage, and we are doing all that we can to keep trains running.”

On Thursday, forecasts are for more heavy showers and torrential downpours returning by 2pm, clearing by the evening but leaving muggy temperatures behind. There should be some relief from the rain on Friday with the rain returning for Saturday.