Flap Track 6,
The nozzle velocities are much higher than that.
Locally, they are just subsonic on most 70s and 80s large turbofans i.e. about 300m/s for the bypass and maybe 450m/s for the hot nozzle.
More recent engines have reduced the velocities a bit principally for noise reasons.
The expansion cone behind the jet expands at about a 7 degree angle, so the velocity reduces considerably with distance.
However, I do recall one test where a pitot rig was put behind an engine at full power to measure the blast about 60-100m away. Confused by the lack of manometer readings, we went outside to find the rig blown into the next field.
Certainly 100mph blasts may exist at some distance, so hold your hat on.