Yes snow will usually melt when the temperature is 42 F out.
If the sun is shining then the snow will usually melt faster because the sun shining on the snow helps to heat the snow up which then melts the snow.
Snow on the ground might melt slower than the snow on things such as cars, roofs etc.
But when the temperature gets to 42 F then at least 1 inch to 2 inches of snow can melt off the ground depending on the sun.
If it's cloudy out then the snow may melt slower but if the sun is shining the snow will usually melt at a faster pace.
Snow on the ground can melt when the surface temperatures reach at least 32 F or above.
Even when the outside air temperature is freezing or below freezing the snow can still melt off the ground once the temperatures get to at least 32 F on the ground.
Snow can also melt off of things such as cars, roofs etc when the temperature is 32 F as long as the sun is shining on the objects which helps to warm the snow and melt the snow.
It was only 30 F out today but we had lots of sunshine and the snow began melting off the roof of my house and garage.
Although some snow is still on the ground but tomorrow the temperature for the high is supposed to be 50 F so the snow on the ground should melt and maybe go away completely.