Sleet can sometimes melt snow when the sleet lands on the snow.
But not all sleet melts snow and sometimes it just adds to the snow and makes a bigger mess.
Sleet occurs when the falling snow melts and then refreezes before the snow hits the ground.
Snow usually does not stick to the ground or surfaces until the temperature is 32 F or below.
But if the temperature of the surface is below 32 F then the snow can sometimes stick when the temperature is 35 F.
I have seen snow stick to the ground when it was 35 F out but then the snow went away soon afterwards.
So if the snow does stick at 35 F it will not stay on the ground too long before it melts into the ground or evaporates.
If there's enough sun the 2 F degrees can melt snow at least a little bit.
However it usually has to be above 32 F for the snow to really begin to melt and go away.
Snow can also disappear through a process known as sublimation which means the snow evaporates without melting so snow can go away without you seeing it melt.
The reason snow sometimes gradually disappears without actually melting is through a process called sublimation.
The Sublimation is when snow or ice evaporates and goes away without turning into a liquid first.
Ice can and does sometimes evaporate without melting into a liquid first.
When ice evaporates without melting into liquid the process is known as sublimation.
Dry ice is a great example of ice that mostly evaporates without melting and it looks like steam when the sublimation of the ice is occurring.
The process of sublimation is most often used to describe the process of snow and ice changing into water vapor in the air without first melting into water.
"Dry ice" is actually solid, frozen carbon dioxide, which happens to sublimate, or turn to gas, at a chilly -78.5 °C (-109.3°F)
Sublimation is the transition of a substance directly from the solid to the gas state, without passing through the liquid state.
An example of Sublimation in the picture below of dry ice going through the process of sublimation which is the process of ice evaporating without melting.