 Typhoon Thad was considered the worst storm to affect Japan in two years. Originating from a monsoon trough, Typhoon Thad was first classified on August 15, 1981 and was upgraded into a tropical storm the next day. Meanwhile, Thad moved north and northeast and attained typhoon intensity midday on August 18. The next day, the storm reached its peak intensity of 80 mph (130 km / h). On August 22, Thad accelerated northward, striking eastern Japan the next day just before weakening to a tropical storm. After passing through the country, the cyclone transitioned into an extratropical cyclone on August 23.
