The balmy weather of last week is set to be quickly forgotten as freezing temperatures, ice and snow sweep in over the next few days.
Forecasters are predicting wintry conditions and changeable weather in the coming days, after parts of the UK woke up to ice this morning.
In the coldest regions of northern Scotland, the mercury plummeted to as low as -5 degrees and even more Baltic weather is expected.
Despite today marking the formal start of British Summer Time, Britons have been warned they will see a return to winter instead.
UK weather: 700-mile wide 'polar plume' as 'Icelandic plunge' set to hit country
Northern England and Scotland in particular will see frosts, and heavy rains will at times turn to hail, sleet and even snow by Tuesday and Wednesday.
The Mother's Day weather today will start off cloudy with patches of rain, but is expected to clear up later on, especially in the southwest.
Temperatures by lunch time will hit highs of 12 degrees on the south coast, although it will be much colder - closer to 5 degrees - further north.
But by Monday and throughout the coming week it will become more overcast and the showers are likely to be more persistent.
The start of the working week will see the mercury dip to as low as 3 degrees across central England, and a band of rain will begin to sweep across the British Isles by the evening.
UK weather: Britain basks in 19C heat - but 'polar plume' to bring Mother's Day snow
Met Office forecaster Craig Snell told The Sun : "Monday will not be a bad day for England and Wales as it will be dry with sunny spells.
"But the rest of the week from Tuesday onwards can be summed up as ‘April showers’.
"And by night, there will be a risk of frost so gardeners need to take note of that!
"Away from the main towns and cities, temperatures will fall down to -1 and -2 degrees at night."
And Met Office meteorologist Becky Mitchell told The Express: “Temperatures fell to around -5 degrees in the countryside this morning and it is a chilly start with a widespread frost for Northern Ireland and parts of northern England too.
“It is a much cloudier picture across the south compared to recent days.
“That blanket of cloud lingering into the afternoon but there is a chance we could see some brighter spells by the middle part of the day.
“Across the north it is a fairly bright day on the whole cloud building as we head into the afternoon but still plenty of sunny spells and for all of us it is a much cooler day than recently."
The cooler temperatures come as a 700-mile wide 'polar plume' from Iceland is set to arrive.
The RAC has warned of wild conditions hitting the Easter getaway as schools break up on Friday.
