I get fascinated sometimes with the records of the natural world - highest wave, biggest elephant, what have you. This article looks at the claims for the highest wind speed ever recorded.
The official highest ground-level speed measured directly for a wind anywhere in the world is from Mount Weather in New Hampshire in 1943 - 231 mph.
The highest verified wind in a tornado (NOT measured at ground level, but at some hundreds of feet from the ground) is 318mph, taken by Doppler radar in Oklahoma City in 1999.
There are two claimants for the Mount Weather record, one from Australia, one from Guam. The highest measurement, from Australia in the 1996 cyclone Olivia, was 113 m/s or 253 mph. In both cases, the records were not accepted officially, in part because the represented speeds more than double the sustained wind at the time, a freakishly unlikely (though not completely impossible) circumstance.
One is tempted to say that there have been higher wind gusts, only no instrument or observer survived to report them. That's probably a true statement, and the continual improvement in weather instruments makes it likely there will someday be a new official record, but for now - Mount Weather rules!