Question #fd393
1 Answer
Temperatures aloft and on the ground.
Explanation:
For starters, sleet is not an official type of precipitation. It is wet snow (snow that is melting as it is falling).
Okay for freezing rain to fall you need solid precipitation to form (snow) and then as it falls it passes through an above freezing layer and melts. The as it continues to fall it the temperatures go back to below freezing. The precipitation will not freeze immediately just because the temperatures are below freezing (we call this super cooled water droplets). The below freezing liquid precipitation will freeze almost on impact when it hits the ground (assuming that the temperature of whatever it hits is also below the freezing point).
Wet snow forms as regular snow but then as it falls it passes through an above freezing layer that extends all the way to the ground. In this case the elevation from where the precipitation starts to melt to the ground is not far enough for it to completely melt. Ordinarily the temperatures at the surface are above freezing.
