沢増水に警戒。視界不良の稜線は慎重に

As of 7 AM, Mt. Poroshiri summit is cloudy with visibility under 1km. The temperature is 7.2℃, feeling like 5.5℃. With over a 9℃ difference from the base, it is already chilly near the summit. Cloudy conditions will persist through the day, with temperatures rising to 10.9℃ by noon. However, light drizzle is expected to begin around 3 PM, with a 73% chance of precipitation, leading to wet and muddy ground conditions.

The primary risk today is the potential for swollen rivers. The afternoon drizzle, combined with the deep primeval forests characteristic of the Hidaka Mountains, means that river levels can change rapidly even with minimal precipitation. On the Nukabira River Course, which involves over 20 river crossings, be acutely aware of the risk of being unable to cross due to increased water levels and be prepared to turn back early. Additionally, poor visibility is likely to persist in the cirque topography near the summit, demanding extreme caution with route finding.

A "rapid temperature drop" risk has been automatically detected, with a 7℃ decrease expected over the forecast period. Be prepared for sudden chilling during your activity by carrying an extra insulating layer from the start. Perceived temperatures will range from 5℃ to 10℃ during activity, feeling even colder on exposed ridges. Waterproof and breathable rainwear, waterproof hiking boots, and spare fleece or light down jackets are essential. As this is a dense bear habitat, do not neglect bear bells and bear spray.

Temperatures will drop further overnight, reaching 3℃ by early morning. Remaining wet can significantly increase the risk of hypothermia. Appropriate gear and flexible responses to changing weather are crucial for climbing Mt. Poroshiri today.