Temperatures dipped overnight and the Met Office is forecasting snow for some parts of Wales over the next 24 hours.
It has snowed heavily in Scotland and Northern Ireland overnight on Tuesday, and forecasters say Wales will be hit by wintry showers with temperatures dropping to -1°C overnight.
And some parts could waken up to snow on Wednesday morning. The Met Office has now issued a yellow weather warning, saying large parts of Wales will see snow with up to 10cm on some of the highest peaks.
The first warning is in place from 8pm on Tuesday until 10am on Wednesday.
It says "Wintry showers are expected to continue through Tuesday night and Wednesday morning leaving surfaces wet and leading to icy stretches developing on untreated surfaces.
"These showers will fall as a mixture of rain, hail and snow at times, the snow mostly over higher ground.
"Some places are likely to see 1-3cm of snow, mainly above 200m, with 4-8cm possible over the higher ground in northwest England, Wales and west Scotland."
The Met Office forecast for Wales on Tuesday says: "It will be cold and windy with sunny spells, but plenty of wintry showers streaming in from the northwest, some falling as snow, mainly over high ground. There is the added risk of a few rumbles of thunder in the heavier showers.
"Tonight, cold overnight with frequent showers increasingly falling as snow over the hills. Some showers may band together, leading to local accumulations of snow and an ice risk by the morning."
Met Officer forecaster John Griffiths said higher regions will be colder, adding that the temperature would "obviously feel a lot colder with the strength of the wind later on".
Welsh forecaster Derek Brockway says: "The next couple of days drier but colder with winds from Iceland.
"Sunny intervals and wintry showers. Some heavy showers with hail, thunder, sleet and snow. A few cm of snow on the hills. More on the Cambrian and Snowdonia mountains."
Here are the areas that could see snow tonight:
South East Wales
Heavy snow is forecast for Abertillery and Ebbw Vale from Tuesday evening into Wednesday morning.
The Met Office weather map for Abertillery (below) shows snow falling between 8pm on Tuesday to 8am on Wednesday.
Elsewhere, Newport, Pontypool, Abergavenny and Caerphilly could all see some snowfall.
The Met Office weather map for Newport (below) shows some snow around 8pm on Tuesday and sleet between 4am and 7am on Wednesday, with lows of 2°C.
Cardiff, Swansea and the Valleys
It doesn't look like people in Cardiff are going to see much snow.
The Met Office weather maps are show some hail showers on Tuesday morning, with shower and sunny spells throughout the day. Temperatures overnight will drop to lows of 3°C.
Some snow forecast with the Valleys with sleet and snow showers forecast for Merthyr Tydfil between 7pm and 9am, and lows of 1°C.
Snow is also forecast for Aberdare between 1am and 6am on Wednesday, before it turns to sleet. It is more likely to fall as sleet in Pontypridd where lows will be around 2°C
No snow for Swansea, which is not unusual, as it rarely seems to settle there like it does in other parts of the country, and no snow for Neath either. Temperatures will drop to lows of 3° here.
South West Wales
Not much snow forecast for this part of the country, with temperatures between 4 and 5°C in Pembroke and Tenby.
Mid Wales
Overnight snow is forecast in many places, especially on higher ground.
The Met Office weather map shows snow in Knighton, Powys, from 5pm on Wednesday and lows of 0°C, and snow in Newtown (below) between 10pm and 8am.
North Wales
Welsh forecaster Derek Brockway says there could be up to 10cm of snow on some of the mountain peaks in north Wales.
In Bala, snow is forecast from 5pm to 6am, with lows of 1°C.
