A Met Office warning for snow and ice on Monday morning now covers most of Wales.
The forecasting service had issued a yellow warning for parts of north Wales on Saturday, but that was updated on Sunday morning to cover most of the country.
It came as Welsh weather presenter Derek Brockway said that pinpointing what areas will see snow has been difficult.
He said: "Looks like some parts of Wales will wake up to a dusting or covering of snow tomorrow morning (Monday, December 28).
"However, pinning down detail, even at this relatively late stage, is proving tricky with differences amongst the models."
He shared pictures of the four models :
The Met Office yellow weather warning is in place from midnight on Monday (December 28) until 6pm.
It states: "An area of rain is likely to move south through Sunday night and Monday across parts of England and Wales.
"There is the potential for this to turn to snow for a time. There is a lot of uncertainty in where snow develops with some areas seeing little or no accumulations.
"However, there is a very low likelihood of 1-3 cm, and locally 5-10 cm falling in a few places, particularly over higher ground of Wales above 200 metres.
"As well as snow, widespread ice may also be an issue, especially where treatment has been washed off road surfaces."
The areas of Wales covered by the warning include:
- Blaenau Gwent
- Bridgend
- Caerphilly
- Cardiff
- Carmarthenshire
- Ceredigion
- Conwy
- Denbighshire
- Flintshire
- Gwynedd
- Merthyr Tydfil
- Monmouthshire
- Neath Port Talbot
- Newport
- Powys
- Rhondda Cynon Taf
- Swansea
- Torfaen
- Vale of Glamorgan
- Wrexham
The latest weather warning comes after Wales was hit by Storm Bella overnight Saturday into Sunday with wind gusts of more than 80mph.
Western Power said about 1,000 homes have been left without power in south Wales, including 480 in Monmouthshire.
Dyfed-Powys Police said road conditions were "treacherous", with many reports of fallen trees.
On the A470, a fallen tree closed the road for time between Builth Wells and Llyswen, and the A40 between Llywel to Llandovery was also closed before re-opening on Sunday morning.
On Saturday evening a gust of 83mph was recorded at Aberdaron, Gwynedd, amid a Met Office weather warning.
Weather in your area:
Here is the five day forecast for Wales from the Met Office:
Sunday:
A wet day for most with widespread showers lingering throughout. These will be heavy at times and possibly wintry over hills. Feeling cold, with clear spells in the morning, but cloud thickens later. Winds easing but remaining breezy. Maximum temperature 6 °C.
Tonight:
Showers are likely to continue through the evening. Overnight a band of heavy, wintry, rain moves across the country from the west, bringing a risk of ice and snow. Minimum temperature 0 °C.
Monday:
A wet morning as showers move in from the west, heavy at times and wintry over hills. Risk of thunder along coasts. Drier for most through the evening. Cold throughout. Maximum temperature 7 °C.
Outlook for Tuesday to Thursday:
Further showers through this period, wintry at times, particularly along coasts. Cold and windy throughout with wintry hazards and freezing fog, lingering in prone locations, likely for most areas.
