A developing area of low pressure is expected to track across Northern Ireland, northern England and southern Scotland on Saturday.
As this runs into colder air, snow is likely to develop, particularly in any heavier bursts of precipitation.
The largest snowfall amounts will be confined to higher ground, with the potential for 10-20 cm of snow above 350 m. Between 100 m and 350 m elevation, a mixture of rain, sleet and snow is more likely, but there is potential for accumulations of 2-5 cm, and a small chance of 10 cm should the precipitation be heavy enough to maintain snow for a longer duration.
With warm air close by to the south, it may be that places in the south of this warning area end up with mainly rain.
There is a small chance of significant travel delays on roads with some stranded vehicles and passengers, along with delayed or cancelled rail and air travel.
On the southern flank of this system, strong winds are expected, the strongest of these are likely to affect coastal and immediately adjacent regions of the west and south of England and Wales.
Gusts of 50-60 mph are expected quite widely, with some more exposed locations seeing wind gusts of around 70 mph, mainly in coastal areas and just inland.