On Friday morning, temperatures across the UK will hover between -2 and 2C and throughout the day are not expected to reach any higher than 6C.
By Saturday, Wales, central and southern England, could see temperatures up to 12-15C.
But heavy rain is also expected at times over the weekend which the Environment Agency says could lead to some localised flooding
Across south-west England and Wales, a Met Office yellow warning for rain says that throughout Saturday 50-75mm (2-3in) of rain could fall widely.
In some parts, such as south Wales and Dartmoor, there could be as much as 125mm (5in) which would be the whole of November’s average rainfall in just a day.