jet stream

noun

Updated on: 19 Apr 2018

Definition of jet stream

: a long narrow meandering current of high-speed winds near the tropopause blowing from a generally westerly direction and often exceeding a speed of 250 miles (402 kilometers) per hour

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Recent Examples of jet stream from the Web

The polar jet stream brings cold-air masses southward, while at the same time pulling warm air north.

— samantha durbin, Washington Post, "Spring in Washington is a wild ride of weather whiplash. Here’s why that happens.," 10 Apr. 2018
These stunning structures are powered by fast jet streams that are visible in the planet’s clouds.

— andrew coates, Newsweek, "NASA Juno Unlocks Secrets of Jupiter's Mega Cyclone Clusters," 8 Mar. 2018
By better understanding these strong jet streams and the gravity field, the Weizmann Institute of Science's Yohai Kaspi said scientists can better decipher Jupiter's core.

— chris ciaccia, Fox News, "NASA releases 'unearthly' pictures of Jupiter, showing 9 massive cyclones with Category 5 hurricane wind speeds," 8 Mar. 2018
The unusual weather pattern is due to a southward dip in the jet stream that's bringing temperatures more than 25 degrees lower than average to areas east of the Rockies.

— carly breit, Country Living, "Break Out Your Jackets—August Is Going to Be Chilly for Much of the U.S.," 2 Aug. 2017
Cold jet stream pattern The reason for the snow showers is some upper-level energy that will be rotating around a system at about 18,000 feet.

— david epstein, BostonGlobe.com, "We’re about to have an unusually cold weekend," 23 Mar. 2018
Another paper reveals that these atmospheric jet streams circulate below each of the zones and belts, and reach all the way down to 1,900 miles.

— andrew coates, Newsweek, "NASA Juno Unlocks Secrets of Jupiter's Mega Cyclone Clusters," 8 Mar. 2018
For starters, the jet stream must be properly positioned in the mid-latitude United States.

— steven senne, National Geographic, "Wind, Snow, and Floods—What You Need to Know About the Northeast's Dangerous Winter Storm," 2 Mar. 2018
Later this week the jet stream will stay further north, Hoover said, allowing Indianapolis to warm up.

— emma kate fittes, Indianapolis Star, "Indy just endured face-numbing cold. Now, temperatures will rise to the upper 50s.," 7 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'jet stream.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of jet stream

1947

JET STREAM Defined for English Language Learners

jet stream

noun

Definition of jet stream for English Language Learners

: a strong current of fast winds high above the Earth's surface

JET STREAM Defined for Kids

jet stream

noun

Definition of jet stream for Students

: high-speed winds blowing from a westerly direction several miles above the earth's surface

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See words that rhyme with jet stream Britannica.com: Encyclopedia article about jet stream

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