Tornadoes in Noda (Chiba prefecture) and Koshigaya (Saitama prefecture)

Noda (30 km from Tsukuba) and Koshigaya (40 km from Tsukuba) experienced tornadoes on September 2nd. Unlike the Hojo tornado in May 2012, which even prompted the JMA to request funding for a new radar tracking clouds every 10 seconds, nobody died.

Previously we had visited the monument of the Dutch civil engineer Rouwenhorst Mulder near the canal he built, close to Noda city. The images now give a different impression. As of now, in both areas combined 67 people are injured and 550 buildings damaged. Some buildings still risk collapsing and 5 shelters are operating.

From the NHK:

Low storm cloud caused tornado

A meteorologist says a tornado that hit parts of eastern Japan on Monday was produced by a supercell -- a thunderstorm containing rotating updrafts of air -- that formed much closer to the ground than usual.

Japan's National Defense Academy Professor Fumiaki Kobayashi said he studied footage of the tornado captured in the Saitama and Chiba prefectures.

The professor said the cloud developed as low as 500 meters from the ground. Such clouds usually form at twice that height.

He said a funnel-shaped airstream appeared under the cloud and grew to at least 100 meters wide.
Kobayashi said the cloud was so large that it maintained power even when the storm lost energy due to rainfall.

He said people in the tornado-hit areas must have thought they could touch the dark cloud. He urged people to be cautious of supercell clouds as they can be a sign that a tornado is coming.

Update: 64 people injured, over 600 houses damaged. More news and videos here. 

At the end of this video there is a commentary by Dr. Takeshi Maesaka, senior researcher of the storm, flood and landslide research unit, monitoring and forecast research department of the NIED in Tsukuba. He gave us a lecture and visit to the radar analysis room at a field trip October 30th, 2012.