- Who
- South Uist
- What
- 656 kilometre(s) per hour
- Where
- United Kingdom (Outer Hebrides)
- When
The fastest jetstream velocity ever measured is 656 km/h (408 mph). It was recorded by instruments onboard a Skua rocket above South Uist, Outer Hebrides, UK at an altitude of 47,000 m (154,200 ft), on 13 December 1967.
