💨 THE JET STREAM: A RIVER OF WIND 10 KM UP
PAGE 1 OF 5, WIND HIGH ABOVE US
SKY RIVER
FAST WIND YOU CANNOT FEEL ON THE GROUND
Far above your head, near the top of the troposphere (about 10 km up), air sometimes races eastward in a narrow band called the jet stream. Winds there can reach about 200 to 400 km/h, much faster than a hurricane at the surface. Pilots on transatlantic flights know this river well: flying with the jet saves fuel and time, while flying against it feels like swimming upstream. You never feel the jet stream while walking to school, but it still shapes the weather you get days later by pushing storm systems along.
✈️ HEIGHT CLUE
Commercial jets often cruise near 10–12 km altitude, right where the jet stream flows.
WHOOSH!
SPEED
🏎️ 400 km/h is faster than most high-speed trains, yet the jet is a wide ribbon of air, not a vehicle.
📊 Weather maps show the jet as thick lines curving across continents.
📊 Weather maps show the jet as thick lines curving across continents.
UP HIGH
🎈 A party balloon at ground level drifts slowly compared with winds ten kilometres above.
🛰 Satellites and weather balloons measure these high speeds for forecast models.
🛰 Satellites and weather balloons measure these high speeds for forecast models.