A tornado that struck Shizuoka Prefecture on Friday was estimated to have been one of the strongest in the country, with an instantaneous wind speed of 270 kilometers per hour, according to the Japan Meteorological Agency.

The estimate, released on Monday based on a field survey by the agency, corresponds to JEF3, the third-strongest level from the top on the six-level Japanese Enhanced Fujita Scale, a measure of tornado intensity.

The tornado swept through an area between the city of Makinohara and the neighboring town of Yoshida, both in Shizuoka. It touched down around 12:50 p.m. on Friday, tearing off exterior wall components of steel-framed stores and snapping utility poles.

Separately, a blast of wind that formed in the city of Kakegawa, also in Shizuoka, about 20 minutes earlier was also likely to have been a tornado, the agency said. It was estimated to have reached JEF2 on the scale, with an instantaneous wind speed of 198 kilometers per hour.

These coincided with Tropical Storm Peipah, which passed along the Pacific coast of Shizuoka on Friday.

As of Monday afternoon, the tropical storm and associated tornadoes and gusts left eight people seriously injured and 81 others slightly injured, according to the Shizuoka Prefectural Government. Two houses were destroyed and 117 were severely damaged, while 1,217 suffered partial damage.

Because tornado wind speeds cannot be measured directly, the JEF scale, developed from the Fujita Scale created in 1971 by the late Japanese-born meteorologist Tetsuya Fujita, estimates intensity based on damage.

A JEF3 tornado was confirmed in 2018 on Ie Island in Okinawa Prefecture. Before the enhanced scale was developed, tornadoes of F3 intensity, the third-highest out of seven levels on the Fujita Scale, were recorded in the cities of Joso and Tsukuba in Ibaraki Prefecture in 2012, as well as in the town of Saroma in Hokkaido in 2006.