• WEATHER
• Weather Fronts
• Clouds
• Thunderstorms
• Tornadoes
• Hurricanes
• Heat Waves
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• Literacy Framework

The majority of tornadoes occur in agricultural areas. Tornadoes need moisture to feed their parent thunderstorms and the instability associated with spring and summer warming. Crops need moisture to grow and the temperature variation associated with changing seasons. Both conditions for tornadoes and agricultural growth are found in the same areas, as is shown on this map. (Courtesy of Dr. T. T. Fujita, University of Chicago)

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The Earth Scientist, Volume XXV, Issue 3, Fall 2009

The Fall 2009 issue of The Earth Scientist includes a collection of Earth and Space Science articles for you, covering the current efforts to save Louisiana’s Lake Pontchartrain, student research into building design as it relates to earthquake damage, an exciting Earth Science project and resource from the United Kingdom...more

Wave Beats

Sound travels in waves. You hear sound because waves hit your ear. Sound waves are similar to ocean waves. They both have a certain frequency. The frequency is measured in hertz, which is one cycle per...more

Chasing Tornadoes

Storm chasers are different than storm spotters. Chasers travel around Tornado Alley looking for severe storms and tornadoes. This area in the Great Plains is the best for chasing because of the frequency...more

Energy Density

A tornado is the most intense force in nature. That doesn't mean it's the most powerful. In fact, a thunderstorm can be 40,000 times more powerful than a tornado. Then why aren't thunderstorms as dangerous...more

The Doppler Effect

The Doppler effect was named after Christian Doppler, who first came up with the idea in 1842. He learned that sound waves would have a higher frequency if the source was moving toward the observer and...more

Tornado Forecasts

It's hard to forecast tornadoes. They don't last very long and are also very complicated. Scientists don't really know how they form, but they do where they tend to form. Using what they know about the...more

Common Tornado Myths

Has someone ever told you to open your windows during a tornado? Or has someone ever told you that you don't have to worry about tornadoes because the place where you live is protected? These are two of...more

Tornado Notification

Tornadoes are very dangerous so it's important to know when they may form so you can take shelter. Forecastors at the National Weather Service are always looking for possible storms. Even though nobody...more