What Is a Polar Vortex? — Reading Comprehension

A polar vortex is a large area of swirling cold air that sits over the Earth’s poles—the North Pole and the South Pole. This air is always present, but it becomes stronger in the winter months. The term “vortex” means a spinning motion, like a whirlpool, and in this case, it refers to a spinning mass of cold air high in the stratosphere.

Normally, the polar vortex stays near the poles and is held in place by strong winds called the jet stream. But sometimes, the jet stream weakens or becomes wavy, allowing part of the cold air to break off and move south. When this happens, areas like the United States, Europe, or Asia can experience extremely cold weather.

A polar vortex is not a storm or a snowstorm itself, but it can lead to dangerous cold snaps, snow, and icy conditions. These changes can affect travel, cause school closures, and even lead to power outages.

Scientists monitor the polar vortex using weather balloons and satellites. Understanding it helps meteorologists predict extreme winter weather and prepare people for sudden temperature drops.

Fun Fact: In 2019, a split in the polar vortex brought temperatures as low as –50°F (–45°C) to parts of the U.S.!

What is a polar vortex?

Where does the polar vortex usually stay?

What keeps the polar vortex in place?

What can happen when the jet stream weakens?

When is the polar vortex the strongest?

What tools do scientists use to study the polar vortex?

What is the main idea of the passage?

What kind of weather can a polar vortex cause?