Gavin Staples wrote:

big snip

I would assume that when the temperature did get above 0C it was
for only a very short time, say an hour or two in the day. This would
have been insufficient to melt the large amounts of snow.

Look at www.winter1947.co.uk Firstly selecting the Charts Master Page and
then following the daily sequence you will observe that there were several
incursions of milder air which cleared, albeit temporarily, the lying snow
from low lying southern areas. Selecting pages for snow depth and days of
snow lying will confirm this. The front shown shown on the 10th February UK
chart was significant as it marked the boundary between relatively milder
conditions to the south and colder air to the north. This failed to reach
N.Norolk hence the persistence of deep snow cover at low lying West Raynham.
Otherwise the snow cover was deepest and most persistent over high ground in
the Midlands, the North East, North Wales and Eastern Scotland.

All the best

--
George in Epping, West Essex (107m asl)
www.eppingweather.co.uk
www.winter1947.co.uk