Ice is expected to form on some surfaces from late Tuesday afternoon and last overnight into Wednesday morning.
The chance of this is highest across parts of Scotland and northern England where rain may fall onto frozen surfaces.
A few centimetres of fresh snow are also likely on high ground, mainly across Scotland and northern England.
There will probably be icy stretches on untreated roads, pavements and cycle paths with some injuries possible from slips and falls.
There is also a very small chance of travel disruption across parts of Scotland and northern England.
A spokesman for the Met Office said: “A band of rain with some snow (mostly on hills) will reach western Scotland and Wales on Tuesday afternoon and move quickly eastwards across all parts through the evening and overnight.
“Whilst a brief spell of snow is likely, mostly on high ground, the main hazard is likely to be icy surfaces where rain falls onto frozen ground.
“This risk is greatest across parts of Scotland and northern England where the impacts could locally be greater than elsewhere.
“Temperatures may then rise a little for a time overnight before falling again by Wednesday morning as cloud clears, so ice remains likely.
“In addition, some wintry showers may affect western Scotland on Wednesday morning.”