今日の斜里岳は山頂付近で曇り、視程1km未満と低い。午前7時半の山頂気温は1.1℃、体感は-2.7℃と冷え込んでいる。山麓との気温差は約4.5℃あり、標高差による温度変化を考慮した行動が求められる。
日中の最高気温は正午頃に4℃まで上がる予報だが、体感は0℃前後で推移する。降水は予報期間中0mmだが、湿度99%と高いため、地面はウェットから泥濘状態と推測される。特に清岳荘起点ループルートの旧道沢ルートでは、滑りやすい岩や泥に注意が必要だ。沢の急増水リスクは低いが、足元は常に濡れる可能性が高い。積雪深は0cmのため、アイゼンやチェーンスパイクは不要だが、防水性の高い登山靴と雨具は必須装備となる。防寒レイヤリングは、ベースレイヤーに速乾性、ミッドレイヤーにフリースや薄手のダウン、アウターに防水透湿性シェルを用意すること。グローブと帽子も携行すべきだ。
自動リスク判定で指摘された【急激な気温低下】に厳重な警戒が必要だ。夕方18時には山頂気温が-2℃、夜間にかけて-6℃まで冷え込む予報が出ている。行動中の気温急変に備え、出発前から防寒レイヤーを1枚多めに携行し、特に稜線に出る新道ルートでは日没後の急激な冷え込みと風の影響を強く受ける。引き返しの判断は早めに行うこと。突風は日中11〜12m/s程度で、強風による行動困難や低体温症のリスクは低いが、長時間の停滞は避けるべきだ。雷の予報はない。ヒグマの生息地であるため、鈴などの対策を怠らないこと。日中の登山は可能だが、視界不良と低温、足元の悪さに十分な注意が必要。日没前の下山を厳守すること。
北海道
斜里岳
Mt. Shari
2026年5月21日 07:24 更新
視界不良と低温 旧道沢は慎重に
Low Visibility and Cold Temperatures Persist. Expect Rapid Cooling by Evening.
現在の気象状況 — Current Conditions
▲ 山頂エリア (Summit)
気温 Temp
+1.1°C
風速 Wind
3.5m/s
NW
天候 Weather
☁️ 曇り
体感 Feels Like
-2.7°C
▼ 登山口・山麓エリア (Base)
気温 Temp
+5.6°C
風速 Wind
2.3m/s
NNW
天候 Weather
☁️ 曇り
標高 Altitude
688m
山頂の3時間予報 — Summit Forecast
09:00
+1°C
3.1m/s
NW
💧 0mm
(4%)
12:00
+4°C
3.4m/s
NW
💧 0mm
(6%)
15:00
+3°C
3.9m/s
NNW
💧 0mm
(0%)
18:00
-2°C
3.5m/s
NNW
💧 0mm
(0%)
21:00
-5°C
2.3m/s
NW
💧 0mm
(0%)
00:00
-6°C
2.1m/s
NNW
💧 0mm
(0%)
03:00
-6°C
1.8m/s
NNW
💧 0mm
(0%)
気象分析 — Analysis Report
日本語
コンディション概ね良好 — 通常の山岳安全対策を実施すること
English
Conditions generally good — Conduct standard mountain safety measures
Today on Mt. Shari, the summit area is cloudy with visibility below 1km. At 7:30 AM, the summit temperature was 1.1 degrees Celsius, feeling like -2.7 degrees Celsius, indicating a significant chill. There is approximately a 4.5-degree Celsius temperature difference between the summit and the base, requiring careful consideration of elevation-related temperature changes.
The highest daytime temperature is forecast to reach 4 degrees Celsius around noon, but the felt temperature will remain around 0 degrees Celsius. Although no precipitation is expected throughout the forecast period, the high humidity of 99% suggests the ground will be wet to muddy. Particular caution is advised on the Kyudo Sawa Route of the Kiyotakeso starting loop route, where slippery rocks and mud are likely. While the risk of rapid stream swelling is low, your feet will likely get wet. With no snow depth, crampons or chain spikes are unnecessary, but waterproof hiking boots and rain gear are essential. For layering, carry a quick-drying base layer, a fleece or light down mid-layer, and a waterproof-breathable shell as an outer layer. Gloves and a hat should also be carried.
Strict vigilance is required for the "rapid temperature drop" indicated by the automatic risk assessment. The summit temperature is forecast to drop to -2 degrees Celsius by 6 PM and further to -6 degrees Celsius overnight. Prepare for sudden temperature changes during your activity by carrying an extra insulating layer from the start. Particularly on the Shindo Route which leads to the ridge, you will be strongly affected by the rapid cooling and wind after sunset. Make an early decision to turn back if conditions worsen. Gusts are expected to be around 11-12 m/s during the day, posing a low risk of extreme difficulty or hypothermia due to strong winds, but prolonged stops should be avoided. There is no forecast for lightning. As Mt. Shari is a habitat for brown bears, do not neglect countermeasures such as bear bells. Daytime hiking is possible, but extreme caution is needed due to low visibility, cold temperatures, and poor underfoot conditions. Ensure to descend before sunset.
The highest daytime temperature is forecast to reach 4 degrees Celsius around noon, but the felt temperature will remain around 0 degrees Celsius. Although no precipitation is expected throughout the forecast period, the high humidity of 99% suggests the ground will be wet to muddy. Particular caution is advised on the Kyudo Sawa Route of the Kiyotakeso starting loop route, where slippery rocks and mud are likely. While the risk of rapid stream swelling is low, your feet will likely get wet. With no snow depth, crampons or chain spikes are unnecessary, but waterproof hiking boots and rain gear are essential. For layering, carry a quick-drying base layer, a fleece or light down mid-layer, and a waterproof-breathable shell as an outer layer. Gloves and a hat should also be carried.
Strict vigilance is required for the "rapid temperature drop" indicated by the automatic risk assessment. The summit temperature is forecast to drop to -2 degrees Celsius by 6 PM and further to -6 degrees Celsius overnight. Prepare for sudden temperature changes during your activity by carrying an extra insulating layer from the start. Particularly on the Shindo Route which leads to the ridge, you will be strongly affected by the rapid cooling and wind after sunset. Make an early decision to turn back if conditions worsen. Gusts are expected to be around 11-12 m/s during the day, posing a low risk of extreme difficulty or hypothermia due to strong winds, but prolonged stops should be avoided. There is no forecast for lightning. As Mt. Shari is a habitat for brown bears, do not neglect countermeasures such as bear bells. Daytime hiking is possible, but extreme caution is needed due to low visibility, cold temperatures, and poor underfoot conditions. Ensure to descend before sunset.
山岳ガイド — Mountain Guide
概要 Overview
北海道斜里郡清里町に位置する標高1,547mの百名山。オホーツク海に裾野を伸ばす独立峰の山容から「斜里富士」とも呼ばれる、知床エリアを代表する秀峰。
特徴・地形 Features
沢沿いに登る旧道（連続する滝の景観）と、稜線をたどる新道のループルートが特徴。山頂稜線は森林限界を超え、北海道らしい広大なパノラマが広がる。
ベストシーズン Best Season
7月〜9月中旬。沢ルートは増水・滑滝注意。残雪期はピッケル・アイゼン要。
主要ルート Main Routes
清岳荘起点・旧道〜山頂〜新道のループ（最一般的）、三井コース。
注意点・危険箇所 Cautions
旧道沢ルートは滝の連続で滑落事故が多発。沢の急増水時は通過不可。ヒグマ生息地。
アクセス Access
JR釧網本線清里町駅から車・タクシーで清岳荘へ。バス便はなし。
※ 本ガイド情報は一般的な参考資料であり、最新の登山道状況・規制情報は各自治体・登山口の公式情報をご確認ください。