The Met Office has issued a yellow weather warning for fog, as the forecaster warned drivers of potentially hazardous conditions on roads on Friday morning.
Dense fog with visibility below 100m is expected in parts of the East Midlands, East of England, London & South East England, and West Midlands, which are under the warning until 10am.
The most extensive and disruptive fog will be during the morning rush hour, and delays to bus and train services as well as flights are possible, the Met Office said.
It is expected to begin lifting slowly later on Friday morning in most areas, but may not clear in rural spots in eastern England until the afternoon.
But the fog is expected to return on Friday evening and across the weekend when it will be more widespread.
Meteorologist Honor Criswick said: “The foggy picture is set to continue as we creep our way closer towards Halloween.”
She said eastern areas of Wales, Lincolnshire, and northeast England could also see some fog on Friday.
“Later into the evening, we will see that fog return, especially across eastern areas of England quite early on into the evening. This fog is likely to be more widespread,” Ms Criswick said.
“Towards the northwest, it’ll remain quite cloudy and quite breezy.”
She said it will also be a “chilly, gloomy” start to Saturday before some sunny spells across England and Wales.
The Met Office said: “Give yourself the best chance of avoiding delays by checking road conditions if driving, leaving extra journey time, or amending plans if necessary.
“Make sure you know how to switch on your fog lights, and check they are working before setting off on your journey. Bus and train services, as well as flights and ferry travel, may also be affected; check for updates from your travel company, and follow their advice.”
Met Office five-day forecast
Today
Fog slowly clearing, though it may linger into the afternoon in places. Otherwise largely bright with some sunny spells and feeling mild. Breezier in the northwest, with rain possible across northwest Scotland.
Tonight
Mostly dry with variable amounts of cloud. Areas of fog, dense in places, developing across England and Wales. Thicker cloud affecting the far northwest of Scotland. Feeling mild.
Saturday
Areas of fog lingering across parts of England and Wales, though some sunny spells will develop. A little rain affecting the far northwest of Scotland, sinking southwards during the day.
Outlook for Sunday to Tuesday
Dry and settled for most, with variable cloud. Widely foggy across England and Wales at first on Sunday, with some fog slow to clear. Similar conditions on Monday and Tuesday.
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