Riding a fast tail wind!

It's not often that I check an airliner's onboard air-flight status. So when I did, I was surprised to see us riding a rather speedy tail wind....

Now maybe I'm just not up-to-snuff about weather patterns at 39,000 feet, but isn't this hurricane-force winds? Is this normal at these altitudes? I'll have to consult my pilot and Boeing friends about this....

At any rate, it was nice to know it was a TAIL-wind rather than a HEAD-wind, pushing our overall speed near 700 mph....

Apparently, at 39,000, that put our plane past Mach 1.0 (i.e. the speed of sound)! Didn't realize passenger planes had that capability....