Thousands of passengers were stuck at Stansted airport on Sunday morning after a major thunderstorm caused flights to be delayed, diverted and cancelled.

The airport was brought to a partial standstill after the storm – which battered the UK with up to 20,000 bolts of lightning and left hundreds of homes without power – hit a refuelling depot.

People were stuck on stationary planes for hours and complained that they were not given proper explanations for the delays or provided with refreshments. One passenger called the situation a “North Korea-esque” information blackout.

@STN_Airport @Ryanair #understaffed on a busy day, causing huge #delays at checkin & security. Passengers rushed to board their flights to find that a lightning strike had taken out the fuel system & all flights are delayed. No warnings on dep. boards & you knew it. #Stansted pic.twitter.com/FcJo7z8p6c — Andy Murphy (@andymurphy73) May 27, 2018

“Due to an earlier lightning strike, the aircraft fuelling system was unavailable for a period this morning,” said a spokesperson. “Engineers have been on site and have now restored the system. However flights may still be subject to diversion, delay or cancellation. We apologise for the inconvenience and advise all passengers to check with their airlines for their latest flight updates.”

“We’ve been on the plane since 7.45,” said Guy Parker, who is on his way to Ibiza. “It’s just being refuelled now. It’s just going take a long time. The 6.05 next to us is just being refuelled so there’s obviously a very long queue.

“In the airport it was just normal: we didn’t realise there was a problem until we were on the plane. Some people got very cross they were allowed on to the plane without being told.”

Scenes in the terminal were described as “stoically British” as queues of more than a thousand people stretched across the airport.

Others claimed that Ryanair, one of the principal airlines at Stansted, was operating with staff shortages that appeared to leave them poorly placed to manage the chaos. “They’ve clearly not got the customer service in place to offer people other options,” said Jack Dadds, whose flight to Brittany was cancelled. “All their flight desks are closed and there is just one small customer service desk with two or three staff. They were asking people to use the app but it isn’t working, so they have now stopped doing that announcement.”

Ryanair were unable to say how many of its flights had been affected. It said customers can get a full refund or free transfer. “We apologise to all customers affected by these disruptions, which are entirely beyond our control,” a spokesperson said.

As passengers seeking a bank holiday getaway were forced to wait, hundreds of homes across the south of the country were left without power after the humid bank holiday weather broke late on Saturday night.

Heavy thunderstorms will continue to affect parts of Wales, southern and central England through Sunday and into Monday morning, the Met Office said. It issued a yellow flood warning after torrential rain poured down overnight with more than an inch of rain falling within an hour on parts of Wales and the Midlands, causing power cuts and delays to trains and buses that are expected to persist throughout the day.

Motorists in the West Midlands and Bedfordshire were warned of the risks of driving on flood-hit roads and 17 alerts were issued for parts of the Thames valley.

Nearly 1,000 properties were left without power across the Midlands, with the majority of outages due to lightning. In Warwickshire, the fire service said five properties were struck by lightning, while in Dawlish, Devon, a telephone box burst into flames after a BT pole was hit.

As the storm progressed, people across the capital and southern England posted images of the lightning on Twitter and Instagram.

The Met Office meteorologist Charlie Powell said there were somewhere between 15,000 and 20,000 strikes across the UK overnight. “Temperatures overnight did not fall much below 15C (59F) or 16C: for the end of May that’s a pretty hot and humid night, so everything was primed,” he said.

“We had some storms coming in from northern France and some building up in the Channel and they sort of spread out and have been working their way in. It looks like there was just one huge area of thundery showers that worked across London just before midnight.”

The London fire brigade said it had taken 505 weather-related calls overnight, although the majority related to flooding and no callers reported any fires started by lighting strikes.