霧雨が続く額平川コースは増水傾向

Mount Poroshiri experiences persistent light drizzle throughout the day, with summit temperatures feeling around 0 degrees Celsius. While the base remains cloudy, a significant temperature difference of nearly 10 degrees exists between the summit and the lower elevations. Continuous precipitation leads to rising water levels in the rivers, particularly along the Ekihiragawa course, which features numerous river crossings. Rocks and soil are generally wet and muddy in many areas, requiring careful footing due to slippery conditions.

For layering, wear a moisture-wicking base layer, a fleece or thin down jacket as a mid-layer, and a waterproof-breathable rain suit (jacket and pants) as an outer layer. Waterproof hiking boots, gloves, and a hat are essential to prevent hypothermia from getting wet. No crampons or microspikes are needed as there is no snow.

Wind speeds are low, posing minimal risk of strong winds or thunderstorms. However, the combination of drizzle, low temperatures, and high humidity increases the risk of hypothermia, especially if one gets wet during sustained activity. Careful temperature management is crucial, particularly during frequent river crossings on the Ekihiragawa course where getting wet is highly probable. Continuously assess river conditions; if crossings become too difficult, do not hesitate to turn back. Temperatures will remain around 1 degree Celsius into the evening, so prepare for cold nights with dry clothes and ample insulation.