Flights at London airports are being disrupted by freezing fog across the south of England this morning.

Heathrow has been the worst affected, with around 100 flights cancelled, while Gatwick’s Twitter page warns of possible delays and cancellations, and advises passengers to check with their airline before going to the airport.

According to the BBC, 37 flights have also been cancelled at London City airport.

Heathrow has a page explaining why fog can affect flights at the airport, including a section entitled “Why can other airports cope with fog but Heathrow can’t?”.

“The vast majority of airports have spare runway capacity so aircraft can be spaced out more during fog without causing delays and cancellations,” explains the airport.

“Heathrow is unusual in that it operates at 98 per cent capacity, with a plane landing or taking off every 45 seconds. Without taking preventative action, spacing flights out more during fog inevitably causes delays and cancellations because there is simply no room to accommodate the delayed flights.”,,

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