Precipitation

What atmospheric conditions are necessary for snow to reach the ground?

• Temperatures above 0°C throughout the troposphere.

• Temperatures below 0°C throughout the troposphere.

• A warm layer aloft and a cold layer near the ground.

• A cold layer aloft and a warm layer near the ground.

What happens when snowflakes fall through a warm air layer that extends to the ground?

• They refreeze into ice pellets.

• They become supercooled raindrops.

• They melt completely into raindrops.

• They remain as snowflakes.

What causes sleet to form?

• Snowflakes melt in a warm layer and then refreeze in a thin cold layer near the ground.

• Snowflakes fall through consistently cold air from clouds to the ground.

• Snowflakes melt in a warm layer and then refreeze in a thick cold layer near the ground.

• Raindrops become supercooled and freeze on contact with surfaces.

What is the defining characteristic of freezing rain?

• It consists of ice pellets that bounce when they hit the ground.

• It is snow that melts and then completely refreezes into ice before reaching the surface.

• It is liquid rain that falls through a thin layer of sub-freezing air and freezes upon impact with surfaces.

• It is snow that falls through an entirely sub-freezing atmosphere.