21 Nov 2011

Fog strikes UK airports cancelling many flights

Weather Presenter

The first widespread dense fog of the season hit much of central and eastern England this weekend. More than 100 flights from London airports were cancelled and others experienced significant delays.

The fog was very thick with many places having a visibility of just 100 metres, making for extremely poor driving conditions, especially on faster routes.

Although the fog cleared from some places on Sunday afternoon, it persisted across much of northeast England, along with parts of East Anglia and southeast England.

Areas of fog highlighted in yellow outline. Image courtesy of NASA/GSFC, Rapid Response.

(Above) Image of fog from Sunday afternoon. Areas of fog highlighted in yellow outline. Image courtesy of NASA/GSFC, Rapid Response.

It was the persistence of the fog in the London area that caused ongoing problems for flights to and from Heathrow, with passengers being advised to check with airlines before travelling.

A spokeswoman for the airport said: “Passengers are being re-booked or put up in accommodation by airlines, while some domestic passengers are being taken in coaches to their destination.”

Why does fog cause delays at airports?

National Air Traffic Services (Nats) which provides air traffic control services for UK airspace explains on its website: "During thick fog, controllers at airports must work to 'low visibility procedures'."

This effectively means that aircraft spacing on approach to landing and during taxiing is increased at times of poor visibility in order to enable airport operations to continue safely.

This reduces the rate at which aircraft can arrive and depart at airports, resulting in delays and cancellations, especially at busy major airports that handle a lot of traffic.

Fog continued to cause further problems on Monday morning, with more flights cancelled, including an early morning departure from Leeds Bradford Airport.

Whilst there was still some fog across eastern parts of England late on Monday morning, Channel 4 News weather presenter Liam Dutton said that conditions would get better.

“Any remaining fog will lift into low cloud through the rest of Monday, with most places seeing improved visibility in comparison to the past few days.”