"People will need to be more vigilant for avalanches and traffic disruptions in mountainous areas with higher risk of heavy snow," said Hiroaki Kawase, a senior researcher at the Meteorological Research Institute, a division of the Japan Meteorological Agency. Heavy snowfalls of 52.1 millimeters or more per day occurred more frequently in Hokkaido and mountainous areas in eastern Japan between November 2021 and March 2022, according to the institute's report released on 18 October. Meteorologists used to call snowfalls of such intensity a "once-in-a-decade" event. However, warmer temperatures have caused more seawater to evaporate, adding moisture to the atmosphere and allowing more snow clouds to form. While these clouds will bring rain in warmer coastal areas, they can cause extreme snowfall events in inland mountainous areas with colder temperatures. The JMA forecasts warmer temperatures and fewer snowfalls this winter. However, it also warns of heavy snowfall events caused by occasional cold snaps and snow clouds.