Which preserves snow best: continuous clear or continuous cloudiness?
 

With a variety of cloud cover conditions in the last couple of days,
it got me thinking: given temps at or just above freezing by day and
no other variables, which would preserve the snow cover best? While
clear conditions might melt the snow to an extent by day, the temps
would be much lower at night, while with cloud the same temp (around
freezing, at a guess) would prevail both day and night, so less chance
of melting by day, but less cold by night.

Nick