Advice for road users
Travelling in fog can be extremely dangerous. Fog can drift rapidly and is often patchy. Warnings of dense fog are issued when visibility is expected to fall below 200 metres. Severe disruption to transport occurs when the visibility falls below 50 metres.
Travel advice produced in association the Highways Agency
Last updated: 8 November 2013
Keep informed of severe weather
Find out more about what to do during dense fog in our infographic.
What is fog and what causes the different types of fog?
Make sure you know what to do when severe weather is forecast