jet stream

American  

noun

1. strong, generally westerly winds concentrated in a relatively narrow and shallow stream in the upper troposphere of the earth.

2. similar strong winds in the atmosphere of another planet.

   jet streams on Jupiter.

3. the exhaust of a jet or rocket engine.

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jet stream British  

noun

1. meteorol a narrow belt of high-altitude winds (about 12 000 metres high) moving east at high speeds and having an important effect on frontogenesis

2. the jet of exhaust gases produced by a gas turbine, rocket motor, etc

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jet stream Scientific  

1. A narrow current of strong wind circling the Earth from west to east at altitudes of about 11 to 13 km (7 to 8 mi) above sea level. There are usually four distinct jet streams, two each in the Northern and Southern hemispheres. Jet stream wind speeds average 56 km (34 mi) per hour in the summer and 120 km (74 mi) in the winter. They are caused by significant differences in the temperatures of adjacent air masses. These differences occur where cold, polar air meets warmer, equatorial air, especially in the latitudes of the westerlies.

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jet stream Cultural  

1. A narrow band of swiftly moving air found at very high altitudes.

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Discover More

Movements of the jet stream have important (but generally short-lived) effects on weather patterns.

Travel time in an airplane can be lengthened or shortened by the jet stream, depending on the direction of flight and the strength of the stream.

Etymology

Origin of jet stream

First recorded in 1945–50

Example Sentences

This high then blocks areas of low pressure and milder, wet weather from pushing across from the Atlantic and the jet stream is deflected further south.

From BBC

It has been preventing any significant shift in the position of the jet stream, and limiting the chance of more settled, drier conditions.

From BBC

Strong high pressure over eastern Europe and Scandinavia has locked in a very cold air mass, while an active jet stream has steered a succession of Atlantic low-pressure systems towards the UK.

From BBC

A recent shift in the jet stream has allowed milder Atlantic air to be ushered in lifting temperatures to around the seasonal average.

From BBC

Over the weekend the jet stream which is responsible for driving and steering weather systems, finally shifted position, allowing areas of low pressure to move in from the south-west and usher in milder Atlantic air.

From BBC