BySarah Keith-LucasLead Weather PresenterPublished22 minutes agoAnother round of cold health alerts is set to come into force on Sunday following a brief break from the weekend's subzero temperatures.
After readings dipped as low as minus 7C early on Saturday, most places on Sunday morning will be milder and free of frost.
Widespread rainfall is likely with hail and thunderstorms possible for parts of Wales and southern England.
Into the new week, the wintry chill is set to return with UK Health Security Agency (UKHSA) cold-health alerts beginning for the north-east and north-west of England and Yorkshire and the Humber from 21:00 GMT on Sunday.
Milder air will arrive on Sunday morning, with temperatures sitting around 2 to 6C for most places, although the coldest spots in central and eastern England may still drop close to freezing.
It follows a bitter morning on Saturday with minus 7.2C recorded at South Newington in Oxfordshire - the lowest temperature of the autumn so far.
As weather fronts move in from the west, areas of showery rain will drift from eastwards across much of the UK through the day.
Image caption, Outbreaks of rain will be fairly widespread by midday on Sunday with the chance of mountain snow in Scotland and thunder and lightning in the south.
The heaviest of the rain first thing is likely to be in Scotland and Northern Ireland as well as south-western parts of England and Wales.
Outbreaks of rain will then become widespread by the middle of the day, with a chance of thundery downpours in the south.
Some disruption is possible due to bursts of heavy rain. Trees will be shedding leaves readily due to the rain and the brisk winds, and these could block drains - leading to localised flooding.
The slightly milder weather will not stick around long.
Beginning at 21:00 GMT on Sunday, UKHSA cold health alerts will come into effect for the north-east and north-west of England and Yorkshire and the Humber lasting until 09:00 GMT on Thursday.
As low pressure clears eastwards on Monday, rain and wind will ease, but colder air will again move in from the north bringing a return to frost and fog.
Temperatures on Monday afternoon will be around 5 to 8C across most of the UK with a noticeable wind chill near eastern coasts.
Image caption, Monday will see temperatures fall back below average and the chilly northerly winds will make it feel colder still
The exception will be the far southwest of England where highs may reach 12C ahead of the next Atlantic weather front bringing rain and wind.
Monday night's wet and windy weather will sweep across many parts of the country with gales likely around western coasts.
The rain may be preceded by a spell of sleet and snow across the high ground including Snowdonia, parts of the Pennines and in the Highlands. Elsewhere, it will be too mild for any wintry weather.
The remainder of the week will be a temperature rollercoaster with alternating spells of mild and cold weather. You can keep up to date with your local forecast by checking BBC Weather online and on the app.
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