The aftermath of a hailstorm in Church Road, Hove as storms hit the Hove, Brighton and Worthing areas of Sussex at the start of the morning rush-hour yesterday. Photo: PA

Hail and thunderstorms described as a “zombie apocalypse” brought flash flooding and travel disruption to parts of Britain yesterday.

The Met Office issued a severe weather warning later yesterday for the southeast of England as more than half a month’s worth of rain fell in an hour in some places.

Forecasters warned that a “deeply unstable airmass” had brought the risk of heavy thundery showers across East Anglia, the South East and London throughout the day.

A lightning strike sparked disruption for rail passengers during the morning rush hour, while firefighters rescued people from homes and cars hit by floods. The lightning hit an electricity sub-station near Hove in Sussex, causing power to the coastal rail route to be cut, according to a Network Rail (NR) spokeswoman. It caused delays to journeys between Worthing and Hove and Brighton, which were expected to last into the afternoon.

Meanwhile trains were not calling at Worthing station in the Hove direction due to flooding in a subway.

London Fire Brigade rescued two women from a car which got stuck in flood water near South Ruislip station, northwest London.

Severe weather includes hail, thunderstorms, flash flooding

Another two people were rescued from a stranded car in Eastcote Avenue in Harrow, the fire service said.

Twenty houses were also affected by flood water in Bedford Road, Ruislip, while up to one foot of water flooded a ground floor flat in Northolt Road, Harrow.

Essex Fire and Rescue Service said it had dealt with 20 incidents in Thaxted, Essex, following flash flooding. Firefighters rescued five people from three neighbouring houses which were flooded, while a road in the town collapsed from the heavy rainfall, it said.

An East Sussex Fire and Rescue Service spokesman said Brighton crews had dealt with a “large number of weather-related emergency calls”, including flooding and lightning strikes.

Morning commuters posted descriptions on Twitter of heavy hail and localised flooding caused by the storms.

Laurence Hill wrote: “Used to be roads. Now rivers of hail. Never seen anything like it.”

Brighton and Hove Police posted: “Localised flooding in Hove and Portslade, some roads not passable. Please do not enter flood water on foot or in cars.”

Brighton station tweeted: “At a stand west coastway #Worthing #Brighton Both ways due to zombie apocalypse.”

South West Trains said Woking-bound trains would not be calling at Esher, Hersham or Walton-on-Thames because of flooding.

A Southern Water spokeswoman said: “Torrential rain fell across Sussex this morning which has led to parts of our sewer network becoming overwhelmed by the sheer volume of water entering it.

“We are doing all we can to help customers affected by this.”

Sussex Police warned drivers to be careful as flash flooding hit Worthing, West Sussex, and Portslade and Mile Oak on the outskirts of Brighton and Hove.

Brighton and Hove City Council’s headquarters also had to close after the basement flooded due to the heavy rain.

The Met Office issued a “yellow” warning of rain – meaning there is a “moderate risk” – for East Anglia, the South East and London. Up to 43mm (1.7in) of rain – more than half the average monthly total for England in July – fell in an hour in part of Suffolk this morning, a spokeswoman said.

The Met Office said 43mm (1.7in) of rain fell in an hour in Great Dunmow, Suffolk, between 4am and 5am.

Meanwhile, 37mm (1.5in) of rain was recorded in an hour in Isfield, Sussex, while 35mm (1.4in) fell in Ardingly, Sussex.

In Northolt, north-west London, 43.4mm (1.7in) of rain fell over a three-hour period this morning and in Santon Downham, Suffolk, 51.2mm (2in) of rain was recorded from 3am to 9am.

The Environment Agency issued a flood warning - meaning flooding is expected – for the Kidbrooke stream at Forest Row, East Sussex.

It said: “Heavy, thundery showers will continue to bring a chance of some localised surface water flooding issues, especially in urbanised areas, across much of south-east England today, with a risk continuing into the early hours of tomorrow morning in the far southeast.”