The Meteorological Agency is warning residents in western Honshu and Shikoku to prepare for heavy rain and strong winds, with a typhoon forecast to approach the region early next week.
As of noon Friday, Severe Tropical Storm Shanshan was moving north at 10 kilometers per hour from its position west of the Mariana Islands. The storm, which is forecast to strengthen into a typhoon by Saturday, had a central pressure of 985 hectopascals, with maximum sustained winds of 108 kph and gusts reaching 162 kph.
Shanshan, referred to by the Meteorological Agency as Typhoon No. 10, is forecast to strengthen as it moves toward Japan. At noon Saturday, the storm is expected to have a central pressure of 975 hectopascals, with sustained winds of up to 126 kph and gusts of up to 180 kph, continuing its northward trajectory. By 9 a.m. Sunday, the typhoon is anticipated to further intensify, with sustained winds of up to 144 kph and gusts of up to 198 kph.
After tracking north, the storm is expected to veer westward, progressing northwest until Tuesday morning with a central pressure of 950 hectopascals. During this time, it is expected to maintain sustained winds of up to 144 kph and gusts of up to 216 kph.
The storm is then projected to turn northeast, approaching or making landfall on the islands of Honshu or Shikoku by early Wednesday morning, potentially remaining at typhoon strength before weakening as it moves over land.
Authorities are urging residents near the typhoon's projected path to brace for severe winds and heavy rainfall, as well as the possibility of lightning strikes, landslides and flooding. Even areas on the storm's eastern flank, farther from its center, could face adverse weather as Shanshan approaches.
Unstable atmospheric conditions due to a trough of low pressure expected to stall over the western side of Japan, and moist air due to flow in from the Pacific high, have resulted in difficulty predicting the path of the typhoon, according to Weathernews.
Those in potentially affected areas are recommended to stay aware of Shanshan’s trajectory. The Meteorological Agency updates the forecast track multiple times each day.