山頂は極寒の視界不良。凍結箇所に注意

Summit conditions on Mt. Fuji are mostly clear, but visibility remains extremely poor, less than 1km. Daytime temperatures will stay below freezing, with a wind chill factor making it feel like -9°C to -10°C. Although there's no snow cover, expect icy patches on the steep volcanic scree slopes and in shaded hollows, indicating some ice-varnished sections. Exposed slopes above the treeline on routes like Yoshida or Fujinomiya will be particularly susceptible to gusts, causing a rapid drop in perceived temperature.

Essential layering includes a quick-drying base layer, a thick fleece or light down jacket as a mid-layer, and a waterproof-windproof hardshell for outer protection. Don't forget insulated gloves, a warm hat, and a neck warmer. Crampons and an ice axe are mandatory for preventing slips on icy sections; microspikes are insufficient.

While no significant alerts were detected by the automated risk assessment, persistent poor visibility poses a high risk of getting lost. Continuously check your current location during your ascent and descent, and avoid pushing limits. The high risk of hypothermia necessitates frequent breaks and diligent efforts to stay warm. The temperature difference between the summit and the base is over -13°C, highlighting the significant environmental change with altitude.

Temperatures will drop further in the evening, with light snowfall expected to begin late at night. Nighttime travel significantly increases the risk of hypothermia and disorientation due to poor visibility, so ensure you descend before sunset.