This paper introduces the abnormal sea states observation records caused by the Typhoons No.0612, 0613 and low-pressures combined with the Typhoon No.0616 and 0617. Observed wave data were obtained from Japanese Nationwide Ocean Wave in formation network for Ports and HarbourS (NOWPHAS) network. Ten of the NOWPHAS 60 wave stations recorded historical maximum observed significant waves during the 3 major events. Both zero-up-cross wave-to-wave analysis and spectrum analysis were conducted to explain those abnormal wave characteristics. Low frequencys wellsw ith significanwt ave periodsl onger than 15 secondsw ere observeda longt he northern Pacificc oasts with several days duration during the Typhoon No.12 attack.
