In addition to causing historic rainfall across the nation Tuesday that forced thousands to evacuate, Typhoon Guchol was distinctive for being the first typhoon in eight years to make landfall in June.
Usually the typhoon season reaches its peak in August and September, when the storms come up from the south and draw a bead on Japan, riding the edge of the North Pacific High, a massive semipermanent “anticyclone.”
“The North Pacific high-pressure system extended northward farther than usual for this time of the year, which caused the untimely landing,” a spokeswoman at the Japan Weather Association said Wednesday.
“Typhoons typically don’t reach so far north and usually head toward the west this time of season, but the high pressure caused it to hit Japan,” she explained.
Stormy weather is likely to prevail over the next few days, with Typhoon Talim making its way toward Japan. The fifth typhoon of the season is expected to turn into a low-pressure system by the time it approaches Kyushu on Friday, but the Meteorological Agency warns that Talim could still bring heavy rainfall combined with the seasonal stationary front.
Nine typhoons made landfall in the last five years, six of them in August or September, according to the agency’s statistics.
But Guchol slammed into Wakayama Prefecture at approximately 5 p.m. Tuesday, becoming the first typhoon to land this year and the seventh-earliest to hit since the agency began keeping records in 1951. The storm brought with it rainfall that reached more than 100 mm per hour in some areas.
Other factors that carried Guchol toward Japan were the Prevailing Westerlies and the jet stream, according to the Meteorological Agency.