Storm Chasing Glossary

A guide to terms used in “The Chasers of Tornado Alley: Touching the Sky”

Barbecue (BBQ) - a style of smoked meat that originated in the US and became especially popular in Texas, eventually spreading northward onto the Great Plains. BBQ has become a favorite cuisine among storm chasers.

Car (automobile) - a car is the single most important tool in storm chasing.

Cloud - moisture in the air that has condensed and become visible.

Dallas-Ft. Worth Metroplex - the largest metropolitan area in Tornado Alley.

EF Scale - the Enhanced Fujita Scale (EF) is a method for determining wind intensity, especially winds within a tornado.

El Reno, Oklahoma - the location of the largest tornado tornado ever recorded, 2.6 miles wide, occurring on May 31, 2013.

Fujita Scale - the predecessor to the EF Scale created by Dr. Ted Fujita.

Gulf of Mexico (sometimes called Gulf of America) - a warm body of ocean residing just to the southeast of Tornado Alley. Warm, moist air from the Gulf provides fuel to drive powerful thunderstorms that develop farther inland. It is a key element that makes Tornado Alley possible.

Hail - a type of frozen precipitation that falls from storms. Hail grows in size as it travels above and below the freeze line multiple times in a thuderstorm. Storm chasers often see hail up to the size of softballs, although larger sizes have occurred.

Lightning - a visible electrical discharge produced by a thunderstorm from one cloud to another or from cloud to ground. Lightning kills more people in the US than do tornadoes.

National Weather Service - a division of NOAA responsible for local weather forecasting and warnings.

NCTCOG - the North Central Texas Council of Governments has analyzed tornado scenarios to better prepare emergency agencies for a major tornado event in the Dallas - Ft. Worth Metroplex.

Rain - moisture condensed from the atmosphere that falls in drops.

Spencer, South Dakota - the location of the deadliest tornado in state history, which occurred on May 30, 1998.

Storm - an atmospheric disturbance involving wind, and sometimes rain, snow, hail, or lightning.

Storm Chaser - A person who tracks storms for research, photography, social media, business, public safety, or curiosity.

Storm Chasing - The pursuit of storms.

Storm Prediction Center - A division of NOAA that is responsible for posting severe weather outlooks and watches for the US.

Storm Spotter - A person who watches the weather and reports dangerous conditions to the National Weather Service or to an Emergency Agency.

Supercell - a “supercell” is a thunderstorm with a persistent, rotating updraft. Supercells produce the most intense tornadoes, giant hail and prolific lightning. They can grow to greater than 10 miles high. Also known as a mesocyclone.

Tempest Tours - a storm chasing tour company based in Texas that began operations in 2001.

TESSA - the Texas Severe Storms Association is a non-profit dedicated to severe weather education and safety. TESSA has delivered multiple presentations on the “DFW Tornado Scenario” which analyzes future major tornado scenarios in the Dallas-Ft. Worth Metroplex.

Texas Tech University - Texas Tech, based in Lubbock, is home to the Debris Impact Facility which tests tornado shelters.

Thunderstorm - a rain-bearing cloud that also produces lightning.

Tornado - a rapidly rotating column of air beneath a storm that is in contact with the ground.

Tornado Alley - a geographical region of high tornado frequency in the central United States stretching from Texas northward to the Dakotas.

Tornado Warning - a warning issued to the public by the National Weather Service indicating the potential of a tornado in a specific area. A warning means a tornado is occurring, or there are indications that one may form.

Wall Cloud - a cloud feature extending below the base of a thunderstorm updraft which sometimes rotates and may offer advance warning of a developing tornado.

Wind - a natural current of air.