The paper presents an analysis of the tsunami arrival time as a result of the earthquake on 11.03.2011 on the Pacific Ocean. For 91 ports arranged along coasts of Pacific, one counted theoretical arrival times of the tsunami and compared it with data real noted on water level gauges of West Coast / Alaska Tsunami Warning Center. Change of the coefficient in the formula for the wave arrival time from 5.0 to 4.72 as the average factor for the ports lying directly on the open ocean waters was proposed. This is of practical importance for the possible procedures to improve forecasting and warning system for tsunami, which are important in maintaining the safety of navigation in the coastal zone of the ocean