
The Met Office has issued a warning of fog from early this evening (Monday 17) until midday tomorrow - some of it "dense and freezing".
They say it will develop from around 7pm Monday evening and persist until Tuesday lunchtime with a risk of visibility falling below 100 metres in some areas.
This could cause hazardous driving conditions and possible cancellations of bus and train services.
Passengers flying out of Gatwick airport should also check for delays or cancellations.