Snow was falling across all of Shropshire on Sunday morning, with more than four inches (10cm) accumulating by 9am in parts of the county.
It comes as riverside areas continue to deal with serious flooding after the Severn and other rivers burst their banks in recent days.
The yellow weather warning for snow covers all of Shropshire, Mid Wales and the wider Midlands and was issued by the Met Office for all of Sunday, with forecasters suggesting snow could fall throughout the day.
By midday most of the county and Mid Wales was covered in white, with snowmen appearing in parks, gardens and fields across the region.
Emergency services have urged people to avoid travelling unless absolutely essential as a result, with many roads in a dangerous condition and bus services facing major disruption.
Police and paramedics were called to a crash on the M54 where a car overturned in the snowy conditions on Sunday lunchtime.
Snow follows flooding in Shropshire:
Council gritters have been out across Telford and Shropshire but the weather alert warns of possible travel delays and potential power cuts in the worst affected areas.
Meanwhile temperatures could drop as low as -7C (10.4F) overnight, with frozen snow likely to cause further hazardous conditions.
And the rapid testing centre at The Place in Oakengates has been closed as a result of the snow, with people expecting to be tested on Sunday told to rebook online.
Meteorologist Simon Partridge said:“ (The Midlands) is where we are going to see the snow lasting the longest.
“The band of snow that came through overnight stalled over the Midlands and will then track its way back over south-east England.
“Our main focus is that it is going to be a really cold night, particularly across central and southern parts of the UK – so the whole of Northern Ireland, all of Wales, most of the southern half of England from the Midlands and southwards.
He added: “Temperatures are expected to dip to between minus 4C (24.8F) and minus 6C (21.2F) quite widely tonight and where we get that snow lying in parts of the Midlands we could see one or two places where temperatures are as low as minus 10C (14F).”
For riverside areas, the snow was building up next to fields, footpaths and roads that remained flooded.
Flood warnings remain in place along the length of the River Severn, which peaked at Shrewsbury on Friday and Bridgnorth and Ironbridge on Sunday.
Although the river is now receding, the water level remains extremely high, some roads and paths are still covered in water as home and business owners continue the clean-up.
Meanwhile Melverley and Pentre, between Shrewsbury and Oswestry, remain cut off after being badly hit by flooding from the Severn/Vyrnwy confluence.
Shropshire Council said it would be reviewing the situation on Sunday "with the hope of restoring access ASAP".
For some residents it is the third time they have been hit by flooding in less than 12 months after two incidents in quick succession last February and March.
So far this year the Severn has remained just below the level reached last year and the record heights reached in the 2000 floods.