We argue that the sudden change of the sign of the difference between the gravity forces of oceantidal bulges on the test masses of two orthogonal arms of LIGO interferometers could be responsible for theLIGO GW150914 event at the time when the relative strainwas measured. The time coincidence of the events at Hanford and Livingston (USA) interferometers is explained by the moving ocean bulge crossing the critical point in the southern part of the Indian Oceanwhere the forces change the sign.The precise position of the critical point is defined by positions and orientations of the two LIGOinterferometers.During the LIGO GW150914 event,the Moon and the Sun were in very close zenith positions in East Africa.The approximate alignment of the Moon and the Sun with the Earth is present also at the time of theLIGO GW151226 and LVT151012 events. The local maxima of tidal forces exerted on the Indian Oceanappear once in a month.The future inclusion of the third Virgo interferometer in Cascina (Italy)proves to be decisive because it cannot produce the time coincident event with the two LIGO interferometerswithin the described scenario.