It follows a 5.7 magnitude earthquake June 4, at almost exactly the same time of day, in same area.
An earthquake with a magnitude 5.9 about 150 kilometres southwest of Haines, Alaska woke up many people in Whitehorse at 4:54 MT this morning, according to the U.S. Geological Survey.
Many Yukoners got a similar wake-up when a 5.7 magnitude earthquake struck about 73 kilometres southwest of Haines at almost exactly the same time of day on June 4.
That event was followed by aftershocks.
The U.S. Geological Survey warns on its website that the same thing could happen this time.
Several people went on Twitter to record their observations.