一日中霧と雨。ロックガーデン道迷い注意

Mount Tomuraushi summit is currently 4.7℃ with a feel of 2.4℃, cloudy with visibility below 1km. The base reports light drizzle at 11.6℃, indicating a significant temperature drop with elevation. Light drizzle to intermittent showers are expected throughout the day, with precipitation probability rising from 75% to 96% by afternoon. Temperatures will gradually fall from 6℃ to 4.4℃, maintaining near-freezing conditions. Essential layering includes a wicking base, a fleece mid-layer, and waterproof breathable outer shell. Gloves and a warm hat are also necessary.

Due to persistent precipitation and high humidity, ground conditions are expected to be wet and muddy across the entire area. The giant rock formations in the Rock Garden will be slippery, demanding careful foot placement to prevent falls. Crampons or microspikes are not needed, but waterproof hiking boots are essential. Low visibility below 1km will persist throughout the day, posing a very high risk of disorientation, a specific hazard of Mount Tomuraushi in dense fog. Navigating the Rock Garden and the vast wetlands around Kita-numa and Minami-numa will be particularly challenging, potentially leading to critical situations reminiscent of the 2009 accident if weather worsens suddenly.

While lightning risk is low, the risk of hypothermia is elevated due to falling temperatures and continuous precipitation. Getting wet will further reduce the perceived temperature, potentially forcing an emergency stop or evacuation. Considering the challenging long course and the risks of poor visibility and hypothermia, extreme caution is advised for any ascent today. Be prepared to turn back. Rain will continue overnight, with temperatures dropping to 1.1℃ by 03:00 on June 23rd, requiring extreme vigilance for extended night operations.