Jet stream
Jet stream: narrow band of very strong upper-atmosphere wind. Blows west to east, along the boundary between warm and cold air masses (AWH 9.4).
| Jet | Latitude |
|---|---|
| Polar | around 50° to 60°N/S |
| Subtropical | around 30°N/S |
- Altitude: roughly FL200 to FL450.
- Strongest in winter: greatest warm/cold contrast.
- Shifts with the sun: north into Canada by summer, south into the US by autumn and winter (AWH 9.4-9.4.2).
- CAT near the jet: see
clear-air-turbulence.
Trap: mixing up flow and shift. The jet always blows west to east; only its seasonal shift is north-south.
References
- AWH 9.4-9.4.2