稜線は東風強く体感は真冬並み

Current conditions on Rishiri Summit (1671.49m) show a temperature of 0.4°C, feeling like -5.5°C due to an easterly wind of 6.75m/s with gusts up to 16.5m/s. Throughout the day, temperatures are expected to hover between 0°C and 2°C, with gusts consistently around 16m/s. As an isolated peak rising directly from sea level, the ridgelines will be exposed to strong sea winds all day, keeping the wind chill below freezing.

Particular caution is advised on the exposed, fragile volcanic gravel terrain from the 9th station to the summit. Strong winds can stir up fine dust and volcanic debris, potentially reducing visibility temporarily. For those ascending via routes like the Odatomari Course, consider the unstable footing combined with wind-induced cold and potential visibility issues near the summit.

To mitigate the risk of hypothermia, essential layering includes a wicking base layer, an insulating mid-layer such as fleece or a light down jacket, and a windproof, waterproof outer shell. Gloves and a warm hat are also crucial. While no precipitation is forecast, making the ground dry to wet, rain gear is still necessary for wind protection. Crampons or microspikes are not required.

Temperatures will drop further in the evening, reaching around -2°C overnight. It is advisable to plan your activities during daylight hours and avoid unnecessary night excursions. Although visibility is currently good, always be prepared for the potential onset of dense fog driven by sea winds, and monitor weather changes closely.