The Met Office has issued a yellow weather warning for dense fog across London and the South East, including the Heathrow area, warning that flights could be delayed or cancelled. The warning came into force at 8:27pm on Friday 6 November and remains in effect until 11am on Saturday 7 November.
According to the Met Office's own warning for the Heathrow area, clearing skies over south east England on Friday evening allowed mist and patchy fog to develop, with forecasters saying this is likely to turn into "increasingly widespread and in places dense fog" overnight. Visibility could fall as low as 100 metres in the worst-affected spots before the fog lifts and clears to mist and haze during Saturday morning.
The warning covers Greater London, Slough, Windsor and Maidenhead, Surrey, Berkshire and Buckinghamshire, placing Heathrow inside the affected zone for the full duration. Thirty-eight other areas across the East Midlands, East of England and West Midlands are also covered.
The Mirror reported on the warning on Friday evening, confirming the same details published by the Met Office: a yellow alert in place from 9pm Friday to 11am Saturday, with forecasters cautioning that bus and train services may also run slower and that motorists should expect reduced visibility on the roads.
Fog is one of the most common causes of knock-on delays at Heathrow because reduced visibility forces air traffic control to space aircraft further apart on approach, cutting the number of landings the airport can handle per hour. Even where flights are not cancelled outright, passengers should expect that an early-morphology fog event like this one can produce delays that ripple through the day's schedule as aircraft and crews fall behind their normal rotations.
As of Saturday morning, no cancellations specific to this fog warning had been confirmed by Heathrow or individual airlines, and the Met Office's "moderate impact" rating reflects a 50 to 75 percent likelihood of disruption rather than a certainty. Passengers travelling through Heathrow on Saturday morning should check their flight status directly with their airline before leaving for the airport, since fog-related delays can appear or clear within a short window.
What this means for your journey: if you are driving to Heathrow this morning, build in extra time in case of slower roads and reduced visibility, and check our public transport page for live Elizabeth line and Underground links if you would rather avoid driving in fog. See our /public-transport/ guide for options, or /parking/ if you are leaving a car at the airport while you travel.