Cloudy and mild for most, rain will spread across western Scotland, moving south to Wales and central parts.
Clear spells will follow, with some blustery showers and strong winds developing, particularly in Scotland.
UK weather forecast for 6am on Saturday
UK weather forecast for 3pm on Saturday
Further south, patchy rain will clear in the morning, giving way to cloudy and windy weather by midday.
More rain will move in the northwest as the day progresses.
The east of the country will see the best of any sunshine.
The wind will continue throughout the day and into the night.
Cloud and some rain will move southeast on Wednesday, generally clearing by the end of the day.
Following this, skies will clear, with colder weather moving in from the north by Thursday.
Scattered blustery showers will then move in, turning wintry in northern parts.
Strong winds in the north could carry the risk of gales.
Moving towards the end of the month, temperatures are set to remain low, with unsettled and sometimes windy weather and only brief milder spells.
At this point, frost could become widespread and severe.
The last week of January will bring the increased likelihood of cold weather, which could establish itself across the country.
At this time, the risk of snow, ice and frost will be greater, particularly in northern parts.
Some milder and wetter interludes are possible, largely in southern areas.
Generally, the cold period will extend into throughout the first week of February and beyond.
UK surface pressure forecast for 12pm Saturday
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