Guchol formed as a tropical depression over the western Pacific Ocean on June 11, 2012, Unisys Weather reported. It strengthened to a tropical storm the next day, and by June 14 it was a typhoon. Guchol reached super typhoon status on June 16 and 17, but weakened back to a tropical storm by June 19. In the latest reports from the Japan Meteorological Agency, Guchol was expected to bring heavy rains and strong winds to Japan on June 19 and 20.
On June 19, 2012, the U.S. Navy’s Joint Typhoon Warning Center reported that Guchol was located roughly 160 nautical miles (300 kilometers) south-southwest of Kyoto, Japan. The storm had maximum sustained winds of 55 knots (100 kilometers per hour), down significantly from 130 knots (240 kilometers per hour) a few days earlier. By June 19, Guchol had forced evacuations in some parts of southern Japan and disrupted air, land and sea travel, The Mainichi reported.
The LANCE MODIS Rapid Response Team posted additional images of Guchol from June 18 and June 16.