Jet stream

Animation of the polar jet stream, with the fastest winds in red and slower winds in blue

Jet streams are fast flowing, relatively narrow air currents found a little below the tropopause, the transition between the troposphere (where temperature decreases with height) and the stratosphere (where temperature increases with height).^[1]^[2] This is about 10 to 15 kilometres (6.2 to 9.3 mi) above the surface of the Earth.

Jet Stream Media

Clouds along a jet stream over Canada.
General configuration of the polar and subtropical jet streams
Cross section of the subtropical and polar jet streams by latitude
Highly idealised depiction of the global circulation. The upper-level jets tend to flow latitudinally along the cell boundaries.
Hurricane Flossie over Hawaii in 2007. Note the large band of moisture that developed East of Hawaii Island that came from the hurricane.
Flights between Tokyo and Los Angeles using the jet stream eastbound and a great circle route westbound.
Impact of El Niño and La Niña on North America
Meanders (Rossby waves) of the northern hemisphere's polar jet stream developing (a), (b); then finally detaching a "drop" of cold air (c). Orange: warmer masses of air; pink: jet stream.
Jupiter's distinctive cloud bands