Snow has fallen in some parts of the country and there is a possibility of more on the way, forecasters say.
Ice, sleet, hail and incidents of “thundersnow” were reported across Greater Manchester, Devon, Cornwall and west Wales, with temperatures plummeting to zero degrees.
Thundersnow storms are normal thunderstorms but with snow rather than rain.
A rare phenomenon, it is caused in the same way thunder and lightning are triggered during the summer, when a pocket of warm air at ground level rises and collides with the colder air above it.
Even though temperatures in the UK are in places, a little under freezing (-7.2C in Braemar in the Scottish Highlands), the air above it is still significantly cooler.
In the summer, this process creates heavy rain showers and lightning storms.
In a cooler winter, the country is pelted with snow instead. The snow contained within the thunderstorm acts to dampen the sound of the thunder and while the thunder from a typical storm might be heard many miles away, the thunder during a thundersnow event will only be heard if a person is within two to three miles of the lightning.
When thundersnow occurs at night the lightning seems brighter - this is because the lightning reflects off the snowflakes.
But the Met Office said the snow was only likely to lie on higher ground in western and north-western areas, with snow in more southern areas expected to clear.
A spokesman for the forecaster said: “What we’re seeing is normal for this time of year. There have been flurries as far south as Exeter but that has been more wet slush and is likely to turn to rain.
“We are expecting showers in western and north-western areas today which could fall as snow on hills.”
He said more snow might be seen on Friday in areas of Wales, Yorkshire, the Lake District and western parts of Scotland.
The Met Office has issued yellow weather warnings of ice for the Midlands, the north of England, Northern Ireland and Scotland.
Over the weekend the snow is likely to turn to rain across the country but there could still be a scattering of the white stuff on higher peaks.