Snow, and Sleet, and Hail - Oh My!

Graupel and virga, too! During the winter, lots of different kinds of frozen precipitation can fall down from the clouds. They aren't the same thing:

Snow consists of clumps of tiny ice crystals that stick together as they fall.

Freezing rain starts falling as snow. However, on the way to the ground, it passes through warm air, which melts the snowflakes. Then they move through a layer of cold air, which re-freezes them into tiny drops of ice.

Sleet is frozen raindrops that bounce on the ground.

Hail is large ice balls that form in the presence of both rain and ice. The rain coats the ice, making the drops larger. As the ice drops fall, the winds push them back up again, where they get an even heavier ice coating. This can happen several times. Eventually, the hail stones become too heavy to be blown around, and they fall to the ground. They can even get to 6-8 inches (15-20 cm) in diameter!

Graupel, or "soft hail" are little balls of snow surrounded by ice.

Virga is rain or ice that never reaches the ground because it evaporates first. You often see virga streaks below clouds; they are particularly obvious at sunset.

Who's Roy G. Biv?

Most of the light around us is white (really, colorless) light. But white light is actually composed of many different colors - in fact, it is made up of all the colors of the rainbow, quite literally. A rainbow appears when light passes through tiny rain droplets left in the air; this usually happens after a rain shower.

Where else can you see rainbows? Well, as this picture of Niagara Falls shows, rainbow can also appear in the mist around waterfalls (those little water droplets again!). Sometimes things made of glass or crystal can also break light up into its many colors. You can also see rainbows on the surfaces of CD's or DVD's (the unlabeled side).

The colors in a rainbow always appear in the same order, starting from the top: red, orange, yellow, green, blue, indigo (dark blue), and violet (purple). Many people remember the order of the colors from the made-up name "Roy G. Biv". But in England, they remember, "Richard of York Gave Battle in Vain", which seems awfully complicated. See if you can make up a sentence in which the words start with the letters R, O, Y, G, B, I, and V, in that order.