Clear skies and light winds tonight will allow temperatures to fall below freezing for many.
Towns and cities will dip to between 0 and -2C, whilst inland rural areas are likely fall to -3 to -5C.
The coldest values look likely across the Midlands, Wales and northern England, where some local frost hollows may dip to -6 or -7C.
Coastal areas will stay several degrees higher, typically just above freezing. East Anglia and south-east England may also hang onto more cloud drifting off the North Sea.
Local freezing fog patches are possible in low-lying spots, particularly near to water courses.
Fronts moving in the north-west will bring thickening cloud, so temperatures may tend to rise later in the night for western Scotland & Northern Ireland, with rain developing by dawn here.
Over the weekend, Braemar in the Scottish Highlands recorded a low of -14C, the coldest UK temperature in 4 years.
Remember, the coldest temperatures of the 'night' commonly occur around dawn, so expect a bitter start to Tuesday. Make sure to grab the thermals if you're out early!