Flash floods occur when large thunder storms drop several inches of water in a short amount of time.

Landslides- the decent of a mass of earth and rock down the mountain slope. They may occur when water from rain and melting snow sinks through the earth at the top of a slope and seeps through cracks in stones and encounters a layer of slippery material inclined toward the valley Earthquakes and volcanoes also are a cause of fast-moving landslides>

Landslides that suddenly rush down a steep slope can cause great destruction across a wide area of land. This can cause flooding from blocking large bodies of water, destruction of buildings, and even death. In Alberta, Canada, in 1903, a mass of about 30.6 million cubic meters slipped from the top of Turtle Mountain and fell to the valley below. The mass of rocks and earth covered over 2 miles of land destroying the entire town of Frank and killing 70 people.

This landslide which occurred in Colorado did its damage by taking out an entire road, and destroying the car of an unsuspecting driver. Fortunately no one was injured.

Drought- a condition of abnormally dry weather within a geographic region where some rain might usually be expected. A drought is much different from a dry climate, which is a region that is normally dry. When droughts occur it affects all of the people in the area. Water-supply reservoirs empty, wells dry up, and crop damage occurs. When a drought is brief it is known as a dry spell. A dry spell usually lasts for 14 days or fewer while a drought may last for years.

In North America one major drought will occur every 22 years. The area most affected are the prairie and Midwestern states. The disastrous drought which occurred in 1933 and lasted until 1935 in the western plains, became known as the dustbowl. The effect of the drought was aggravated by over cropping, overpopulation, and lack of timely relief measures.