トムラウシ快晴。残雪と稜線は冷たい風

This morning at 7 AM, Tomuraushi summit is clear with a temperature of -0.5°C, feeling like -5.7°C. Gusts reached 21.6 m/s. There is a significant 11.2°C temperature difference between the summit and the base, highlighting the impact of elevation. While temperatures are forecast to rise to 4°C by noon, the wind chill factor will keep the perceived temperature below freezing for extended periods. With wind speeds around 5 m/s and gusts near 20 m/s, it will feel like -5°C to -10°C.

For layering, a wicking base layer, a fleece or light down mid-layer, and a windproof and waterproof shell are essential. Carry extra insulation for temperature regulation during activity. The snow depth is 187 cm. Due to daytime warming and nighttime freezing, areas like the Kitnuma and Minaminuma wetlands and the Lock Garden rock formations are likely to have a mix of residual snow and icy patches. Expect an icy surface where snow has melted and refrozen.

Mandatory equipment includes 10-point or more crampons and an ice axe; microspikes are insufficient. The risk of hypothermia from strong winds and cold air is ever-present. Gusts can cause a rapid drop in perceived temperature. Learning from the 2009 accident, exercise extreme caution for sudden weather changes and be prepared to turn back early. Lightning risk is low. After 6 PM, temperatures will drop below freezing again, increasing the risk of slipping on icy surfaces if your activity extends into the evening.