Thousands of commuters trying to vote in the referendum were affected by flooding as severe transport delays caused by torrential rain and flooding in London.
The Electoral Commission confirmed the 10pm deadline was set in stone, meaning many commuters in London and the South-east could have missed out on casting their votes.
Britain’s busiest station, Waterloo, was among those packed with frustrated commuters amid cancellations and delays caused by the severe weather conditions.
“I have never seen anything like Waterloo Station this evening and I have commuted for over 10 years!” George Franks wrote on Twitter.
If people had failed to join the queue at their polling station by 10pm, they would have missed their chance to vote, the Electoral Commission confirmed to The Independent.
A Leave campaign source said that while it would be “very concerning” if people had been unable to vote as a result of travel disruption, there had been no calls from within the camp for polling stations to stay open.
Wycombe MP Steve Baker, a senior Conservative leave campaigner, said there had been no question of an extension, and that getting voters home in time was the responsibility of the railway service providers.
The weather disruption could also delay some overnight declarations, the Electoral Commission said.
“Because of poor weather, transport of ballot boxes to count centres might take different routes. Weather issues mean it might mean ballot boxes take a little longer to get to counting areas. We’re still looking at declaration being made tomorrow morning.”
South West Trains apologised for the disruption, which has also caused severe delays on eight London Underground lines and the temporary closure of Monument, Cannon Street and Ruislip Manor stations.
“Floods, travel chaos, polling station disruption," tweeted Patrick Strudwick. "Lower voter turnout = Brexit more likely. Rain will end our membership of EU. HELL.”
However, some campaigners said they were staying positive despite the weather conditions.
“The rain isn’t dampening our enthusiasm to campaign for Remain. You’ve got until 10pm to vote,” Labour leader Jeremy Corbyn tweeted.
The amber “be prepared” warning came on a day in which the London Fire Brigade received a day’s worth of calls in 90 minutes.
Some polling stations, including one in Chessington, Surrey, were forced to change location at the last minute when they were flooded or roads leading to them became deluged with water.
Louise Wann, a voter from Middlesex, said the road to her polling station was completely flooded, so she had decided to go to the pub instead.
“My fiancé said he'll give me a piggy back so not to ruin my shoes,” she told The Independent.
The law was changed in 2013 to allow people “in the polling station, or in a queue outside the polling station” to vote after the polls had officially closed.
This was to avoid a repeat of events at the 2010 general election, in which long queues caused hundreds to be excluded from the voting process as they could not enter the polling station in time.
Some have called for a switch to online voting to avoid similar scenarios in future.
“Chaos on transport systems in South East means many may not be home in time to vote in #EUref. It’s high time online voting is introduced!” wrote Green Party activist Andrew Durling on Twitter.
The Rail Delivery Group, which represents train operating companies and Network Rail, told passengers to “consider travelling earlier if they can, in order to get home”.
The worst-affected line was between London Liverpool Street and Ilford, the main route serving Essex and East Anglia. It was closed for most of the day because of flooding at Manor Park. During the evening rush-hour it re-opened, but with speed restrictions in place.
All ticket restrictions have been lifted by Abellio Greater Anglia, and tickets for Thursday will also be valid on Friday.
From Victoria, the Gatwick Express was out of commission for most of Thursday morning, because of flooding in south London. When it restarted, some journeys took three times as long as the timetabled 30-minute run.
Airlines including British Airways, easyJet and Ryanair pre-emptively cancelled dozens of flights linking the UK with France, Spain, Switzerland and Italy because of the stoppage by controllers of the busiest skies in Europe.
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