I've replayed the full comms recording of EHAM TWR on the afternoon of July 25. Between 11:20 UTC and 14:10 UTC, I counted 20 go-arounds on RWY27.
At around 12:15 UTC, the vast majority of approaching aircraft made a go-around because of windshear.
View EHAM traffic, starting at 11:30 UTC:
http://www.flightradar24.com/2015-07...x/52.3,4.74/12
There were single-runway operations on RWY27. PIREPs from aircraft on approach to RWY27 reported windshear of 20 knots at 200 ft and moderate turbulence. There were no windshear reports from aircraft departing from RWY27. Some aircraft cancelled take-off from RWY27 because gusting exceeded 50 kn (from 290 - 310 deg).