山頂日中穏やか。夜間は霧雨に注意

The summit currently experiences thin clouds with a felt temperature of 3.8 degrees Celsius. During the day, expect conditions to transition from thin clouds to mostly clear skies, with temperatures rising to 9.9 degrees Celsius by noon. Winds will generally be light, with gusts peaking at around 10 meters per second, which should not significantly impede movement. There is no snow cover, and the ground is primarily dry. However, high humidity and a forecast of light drizzle overnight suggest that the white volcanic gravel slopes above the tree line may become damp and slippery in places.

For your activity, a moisture-wicking base layer, a mid-layer such as fleece, and a windproof, waterproof outer shell are essential. Carry an insulating layer, like a down jacket, for breaks and to cope with cooler morning and evening temperatures. Crampons or microspikes are not necessary. However, rain gear is mandatory for protection against the forecasted light drizzle overnight and as a wind barrier. Given Mount Ontake's status as an active volcano, carrying a helmet is always recommended.

Towards night, light drizzle is expected intermittently, and temperatures are forecast to drop to 3.4 degrees Celsius. While visibility is good during the day, it may deteriorate during the night's drizzle. Although the risk of hypothermia is low, avoiding prolonged stops in wet conditions is crucial. Daytime activities are feasible without major concerns, but for nighttime excursions, ensure thorough preparation for reduced visibility and wet conditions, and prioritize a conservative approach.