An example of a hook echo.
Click on image for full size
NWSFO/Tuslas, OK

Tornado Forecasts

Tornadoes are hard to forecast. They don't last very long so there's not much time to figure out what's happening. Also, scientists don't really know how they form. They know what the weather's like when past tornadoes have formed, so that's what they use to make forecasts.

Meteorologists take measurements of the air called soundings. One of the things these measurements tells them is how stable the air is. Other measurements tell them the temperature and humidity. Using these measurements, meteorologists can tell if tornadoes are likely to form. When an area looks like it might get hit, they issue a tornado watch.

By using a new kind of weather radar, meteorologists can detect a tornado as it's forming--up to 20 minutes before it forms a funnel! Using conventional radar, they might have been able to see the tornado after it already formed. (A tornado would show up as a hook echo.) That doesn't leave much time to issue a tornado warning. Also, tornadoes don't always show up on radar. Tornado spotters are needed to give reliable observations of the weather. The more time people have before a tornado, the fewer people will be hurt or killed because they'll have more time to seek shelter.

You might also be interested in:

Ready, Set, SCIENCE!: Putting Research to Work in K-8 Science Classrooms

What types of instructional experiences help K-8 students learn science with understanding? What do science educators teachers, teacher leaders, science specialists, professional development staff, curriculum designers, school administrators need to know to create and support such experiences?...more

Tornado Notification

Tornadoes are very dangerous. This is why it's important to know when they are going to form. Forecastors at the National Weather Service are always looking for storms that could pop up. Nobody knows exactly...more

Tornado Lookouts

Meteorologists use radar to forecast where tonadoes might form. But, the radar can't detect actual tornadoes. People are needed for that. That's a problem because people without any training don't know...more

Tornadoes

Tornadoes form from severe thunderstorms. They are very destructive because they have a high energy density. They also don't last very long. This makes it hard to learn about them. Since scientists don't...more

Tornado Stats

Most of the world's tornadoes happen in the United States. These tornadoes are around Tornado Alley. There are about 750 tornadoes each year in the U.S. An average of about 100 people are killed each year...more

Tornado Safety

It is important to be ready for tornadoes because they are very dangerous. You and your family should make a plan for where you should go to be safe if there is a tornado where you are. Most places like...more

Wave Beats

Sound travels in waves. When the waves hit your ear, you hear a sound. Have you ever noticed the waves in the ocean? They go up and down, up and down. Sound waves act the same way. The number of times...more

Chasing Tornadoes

Storm chasers are different than storm spotters. Chasers travel around Tornado Alley looking for severe storms and tornadoes. Sometime there are dozens of chasers following the same storm. All kinds of...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