On 27 May 2018, four losses of separation on final approach during use of dependent parallel landing runways occurred within 30 minutes at Madrid following a non-scheduled weather-induced runway configuration change. This continuing situation was then resolved by reverting to a single landing runway. The Investigation attributed these events to “the complex operational situation which had prevailed following a delayed decision to change runway configuration after seven consecutive go-arounds in 10 minutes using the previous standard runway configuration. The absence of sufficient present weather information for the wider Madrid area to adequately inform ATC tactical strategy was assessed as contributory.