Shop Windows to the Universe

Hands On Mineral Identification helps you to identify over 14,500 minerals! By M. Darby Dyar, Ph.D. See our DVD collection.


Precipitation (pre-sip-uh-tay-shun) is any form of water that falls to the Earth's surface. Different forms of precipitation include drizzle, rain, hail, snow, sleet, and freezing rain.

Precipitation is important because it helps maintain the atmospheric balance. Without precipitation, all of the land on the planet would be desert. Precipitation helps farmers grow crops and provides a fresh water supply for us to drink.

Precipitation can also be damaging. Too much rain and snow can cause severe flooding and lots of traffic accidents. Hail can damage crops and cars. Freezing rain and sleet can destroy trees and power lines.

The opposite of precipitation is evaporation.

Last modified October 2, 2008 by Becca Hatheway.

Shop Windows to the Universe Science Store!

Cool It! is the new card game from the Union of Concerned Scientists that teaches kids about the choices we have when it comes to climate change—and how policy and technology decisions made today will matter. Cool It! is available in our online store.

Windows to the Universe Community



You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more


Drizzle is very light rain; the water drops that make up drizzle are smaller than rain drops. Drizzle can be so light that only a millimeter of water falls to the Earth's surface in one day. It is produced...more


Raindrops form when tiny water droplets collide together in clouds to form bigger ones. When they get too heavy, rain falls out of the clouds. Rain is more than 5mm in diameter. The types of clouds that...more

Sleet and Freezing Rain

Sleet forms when a partially melted snowflake or raindrop turns back into ice as it is falling through the air. Sleet starts out in a cloud as a snowflake or a raindrop. It may be a snowflake or a raindrop,...more


Have you ever left a glass of water out for a long time? Did you notice that the water disappears after a few days? That's because it evaporated! Evaporation is when water passes from a liquid to a gas....more

Make It Rain!

Here's a neat experiment that makes rain in a jar. Plus you get to tell your parents or teacher what to do! You will need a parent or teacher, a jar with a metal lid, 1 cup of water, a hammer, a nail,...more


Stratocumulus clouds belong to the Low Cloud group. These clouds are low, lumpy, and gray. These clouds can look like cells under a microscope - sometimes they line up in rows and other times they spread...more

Martian Clouds

Unlike the Earth, where clouds are found around the entire globe, on Mars, clouds seem only to be found near the equator, as shown in this Hubble telescope image. This may be because water of Mars may...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA