Term

jet stream

Daniel MarkFounder & Editor, Aviatopia
Published Mar 1, 2026Updated Mar 1, 20261 min read

A narrow band of high-speed winds (typically 80–200+ knots) found near the tropopause — affects flight times, turbulence, and fuel planning.

aviation-glossary

Quick Facts

Type
Atmospheric Phenomenon
Definition
A narrow band of high-speed winds (typically 80–200+ knots) found near the tr...
Used By
Dispatchers, Pilots

Definition#

A jet stream is a narrow, concentrated band of strong winds in the upper troposphere or lower stratosphere, usually flowing from west to east at speeds of 80 to 200+ knots.

Why It Matters Operationally#

Airlines ride jet streams to reduce westbound flight times and fuel burn, while routing around or above them on eastbound flights. CAT is frequently found near jet stream boundaries.

See Also

Used in