Weather warnings were in place on Friday morning after dense fog cloaked parts of southern England.
A chilly start for many carried the risk of potentially troublesome patches of fog as temperatures dipped as low as -3.3C (26F) overnight.
Thermometers were expected to bounce back into double figures across the board with highs of up to 16C (61F).
There is the risk of some travel disruption across a swathe of southern England on Friday morning due to patches of dense fog.
The Met Office has issued a yellow warning for fog stretching from Cornwall to London and Kent that will be in place from 5am until 11am.
Forecasters said not everywhere would be affected, but some dense patches could reduce visibility to as low as 50 metres in a few places.
Met Office meteorologist Craig Snell said: “It will be another mild day for many parts of the UK.
“People getting out first thing this morning might think it’s a bit nippy out there and there are some fog patches in central and southern England.
“But there will be a lot of sunshine around later once that clears.”
The unseasonably mild weather saw the warmest Valentine’s Day in more than 20 years on Thursday with a maximum of 16.1C (61F) recorded in the Welsh town of Bala, Gwynedd.