Latest model runs suggest a cold spell is on the way between Christmas and the New Year. However a white Christmas in Wales now looks unlikely despite promising signs earlier this month.
Both the European ECMWF and US GFS models suggest a shift towards colder and drier weather in the run-up to December 25. If this persists, weather experts believe it could usher in some wintry spells heading towards the New Year.
As high pressure settles over the UK during Christmas week, the most likely scenario is dry and colder conditions with increased potential for fog and frost. If this materialises, the more settled outlook will be a relief after weeks of wind and rain.
There is some uncertainty over how long the high pressure will persist. But at this stage, forecasters expect cooler air to flood in from the east after Christmas - and this may remain well into January.
The ECMWF indicates overnight temperatures could fall as low as -4C in parts of Gwynedd on Sunday, December 28. More widely, current model runs indicate widespread frosts across Wales towards the end of the year.
Traditionally, these conditions were not unusual for the time of year. Recent trends have been different however: according to Netweather expert Ian Simpson, the last four years have been mostly mild over Christmas to New Year. "Sometimes exceptionally so," he added.
Weeks of south-westerly winds have left the near Continent too warm to usher in the conditions needed for widespread snow in the UK. But if temperatures continue to fall away, this could lead to wintry spells at the turn of the year, said Mr Simpson. Join the North Wales Live Whatsapp community now
He added: "The more stable high pressure conditions are likely to lead to continental Europe cooling down, making any subsequent easterlies or north-easterlies more likely to be potent.
"Although the run up to Christmas is still 10 days away and subject to change, it is looking increasingly likely that the current mild, wet and windy spell of weather will finally break down in about 10 days' time."
In this week's forecast for Wales, the Met Office said the weather is set to remain unsettled for a while longer. By Wednesday and Thursday, coastal gales are likely and rain is set to be "heavy and persistent". Already, a weather alert for rain has been issued for South Wales.
More showers or longer spells of rain are possible on Saturday, December 20. But, over the weekend, the weather is expected to become gradually more settled.
In its UK outlook, the forecaster said: "Into the following week, high pressure is expected to become more widely established. Winds will be light and clearer skies are likely, however this does not rule out the odd shower, especially around coasts.
"High pressure and settled weather will result in temperatures falling to closer to average, with overnight frosts and morning fog which could be slow to clear."
Currently, the Met Office expects this theme to continue into 2026. In its long-range outlook for December 29 to January 12, the national forecaster said: "High pressure will probably remain influential across the UK during this period.
"This means an increasing likelihood of dry weather compared to the winter so far. Despite the greater signal for settled weather, showers or occasional bands of rain are still possible at times, especially later in the period towards January. These could be wintry in nature.