A yellow weather warning for Saturday has been extended to south-east England.
The Met Office first briefed people in the East Midlands, east of England, north east, Wales and Yorkshire and Humber on Friday to brace for thick fog and freezing temperatures.
But the dangerous weather is now expected to affect more southern regions as well.
Last night the Met Office urged everyone to “get the hot water bottles ready as it’s going to be a cold and frosty night”, with the following statement, adding: “Tonight (Friday) patches of mist will form and continue to spread across Night.
“Some dense nebulae are possible, with visibility possibly dropping to 50-100m in some places. Conditions should slowly improve on Saturday, although some areas of fog east of the warning area may persist into the afternoon.”
Poor visibility can lead to dangerous driving conditions in some areas, slower travel times for car journeys and possible delays in bus and train services.
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