A weather warning has been issued throughout London as severe fog has lead to visibility of less than 100 metres. 

The Met Office have issues a yellow freezing fog warning, saying that it's likely the fog could persist well into the evening.

Driving conditions are expected to be difficult with long delays on roads and cancellations for flights.

A spokesman for Heathrow Airport said: "Heathrow is still in heavy fog, which is expected to continue into the afternoon.

"As of 9.30am, approximately 30 flights have been cancelled. Our advice to passengers is to check the status of their flight with their airline before coming to the airport."

The Met Office say that the fog will slowly lift and thin throughout most areas throughout the day but that it is likely to persist longer of south east England.

The AA urged "extreme caution" for those heading out on the roads, adding that extra time should be allowed, tyres properly inflated and windscreens adequately de-iced.

Spokesman Ian Crowder said on Thursday: "We have got the worst possible conditions really, of fog and icy roads, and that can be lethal.

"I think the message is extreme caution and to prepare for the worst and make sure all windows are clear."

Dr Deborah Turbitt, from Public Health England London, said: “Every winter thousands of people die because of their exposure to cold weather and doctors’ surgeries, hospitals and other parts of the NHS are kept busy as people fall ill - that’s why it’s really important that we all do everything we can to ensure everyone stays well this winter.

“Think about how the coming cold temperatures may affect your friends, family and neighbours, particularly if they are older or very young or have pre-existing health conditions.

“These groups can be particularly at risk from the ill-effects of cold so think now what you could do to help. Keeping homes heated to at least 18C is a great way to avoid the health problems from cold, as is stocking up on food and medicine before cold weather sets in and wearing lots of thin layers instead of fewer thick ones.

“Much of this is common sense but there are people at very real risk when temperatures drop. Now is the time to think about what we can all do for ourselves and others.”

Send in your photos of the foggy weather to joe.dempsey@newsquest.co.uk