The Met Office has issued a warning of freezing fog as temperatures plummet across the UK.
Forecasters say to expect dense fog until 1pm today in northern parts of Merseyside and Warrington.
Many woke up to a thick covering of cloud across Liverpool and Wirral this morning and a very chilly -3°C.
But more is on the way as it makes its way up from the south, although temperatures will rise a little to 3°C at times.
It is also predicted to rain this evening, but then remain cloudy and dry into tomorrow morning.
They said to expect slower journey times with delays to bus and train services possible and there is a chance of delays or cancellations to flights across the region.
The Met Office said: "The fog that has started to form in the south of the warning area will become more widespread during Tuesday evening and night.
"Fog is likely to be dense in places with visibility less than 100 metres, which may lead to some travel disruption and slower journey times.
"Fog will clear in the south and west of the area during Wednesday morning, but may persist until early afternoon in the north and east."
Advice for road users when travelling in fog