A thunderstorm is a rain shower during which you see lightning and/or hear thunder. Since thunder comes from lightning, all thunderstorms have lightning.
Thunderstorms are most likely in the spring and summer months and during the afternoon and evening hours when it’s warm, but they can occur any time of the day and any time of the year.
Thunderstorms are a lot like us. They have three stages in their lives: the Development Stage, the Mature Stage and the Dissipating Stage.
And it takes three things to create a thunderstorm: moisture, instability and lift in the atmosphere. Look for a big, white, pillowy cloud that is being pushed upward by a rising column of air to identify a thunderstorm being born. The cloud will look like a tower (called towering cumulus) as warm air rises into the stratosphere. During the Development Stage, there is no rain or lightning — yet!
When it begins to rain, then you know that the thunderstorm has reached the Mature Stage. The updraft continues to feed the storm with warm air, but precipitation begins to fall out of the storm, creating a downdraft (a column of air pushing downward). When the downdraft and rain-cooled air spreads out along the ground it forms a gust front, or a line of gusty winds. This is when you’ll want to find shelter because mature thunderstorms can cause hail, heavy rain, frequent lightning, strong winds and tornadoes.
Eventually, the thunderstorm runs out of energy and enters the Dissipating Stage. Rain decreases but lightning is still a danger. The thunderstorm fades away and blue skies return.
While our storm may have dissipated, there are many others. As you’re reading this, there are roughly 2,000 thunderstorms in progress around the world. In the United States, we get 100,000 thunderstorms each year. Storms live and die every day.
So, keep your eyes on the sky and watch for thunderstorms being born. Here’s a trick to figure out how far storms are from you.
1. After you see a flash of lightning, count the number of seconds until you hear the thunder. (Use a stopwatch or count “One-Mississippi, Two-Mississippi, Three-Mississippi,” etc.)
2. For every 5 seconds the storm is one mile away. Divide the number of seconds you count by 5 to get the number of miles.
Make sure you do this from a safe shelter. Remember to cease all outdoor activities and go indoors when thunder roars. Thunderstorms are dangerous in every stage of life!
