苗場山山頂は午前中快晴、風も穏やかで、山頂台地の広大な湿原散策には絶好の条件が整っている。山麓とは約7℃の気温差があり、行動中は涼しく感じられるだろう。速乾性のベースレイヤーに、着脱しやすいフリースなどのミッドレイヤーで調整し、快適な登高を心がけたい。
しかし、午後は天候が下り坂となる。15時頃から弱い霧雨が始まり、18時には霧雨となる予報だ。これに伴い視程が低下し、山頂台地での濃霧道迷いのリスクが高まる。特に湿原内の木道は濡れて滑りやすくなるため、湿原内の木道外踏込み禁止を厳守し、足元に十分注意して行動すること。防水透湿性の雨具は必ず携行し、早めの着用を。
山頂の体感気温は15℃前後で推移するが、霧雨と風速12m/s程度の突風が加わると体感は一層冷え込む。低体温症のリスクは低いものの、濡れと冷えへの備えは万全に。雷の兆候はなく、強風も行動を妨げるほどではないが、午後の視程低下を考慮し、早めの行動開始と下山を推奨する。
新潟県・長野県
苗場山
Mt. Naeba
2026年7月24日 07:03 更新
快晴の湿原散策 午後は霧雨に注意
Naeba Summit: Clear Morning for Plateau Exploration. Afternoon Drizzle Risk.
現在の気象状況 — Current Conditions
▲ 山頂エリア (Summit)
気温 Temp
+15.8°C
風速 Wind
0.7m/s
W
天候 Weather
☀️ 快晴
体感 Feels Like
+16°C
▼ 登山口・山麓エリア (Base)
気温 Temp
+22.7°C
風速 Wind
0.5m/s
NW
天候 Weather
☀️ 快晴
標高 Altitude
1,006m
山頂の3時間予報 — Summit Forecast
09:00
+17°C
1.3m/s
WNW
💧 0mm
(75%)
12:00
+17°C
1.8m/s
NW
💧 0mm
(100%)
15:00
+16°C
2.1m/s
NNW
💧 0.1mm
(100%)
18:00
+14°C
1.9m/s
NW
💧 0.9mm
(100%)
21:00
+14°C
1.6m/s
NW
💧 0.3mm
(25%)
00:00
+13°C
1.6m/s
NW
💧 0mm
(2%)
03:00
+13°C
1.9m/s
NW
💧 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
Mount Naeba summit currently enjoys clear skies and light winds this morning, presenting ideal conditions for exploring the extensive wetlands on its summit plateau. There is a temperature difference of approximately 7°C between the summit and the base, ensuring a cool and comfortable ascent. For layering, a quick-drying base layer combined with an easily adjustable mid-layer like fleece is recommended to maintain comfort during your hike.
However, the weather is expected to deteriorate in the afternoon. Light drizzle is forecast to begin around 3 PM, intensifying to a steady drizzle by 6 PM. This change will likely reduce visibility, significantly increasing the risk of getting lost in dense fog on the summit plateau. The boardwalks across the wetlands will become wet and slippery; therefore, strictly keep to the boardwalks and exercise extreme caution with your footing. Carrying full waterproof and breathable rain gear is essential, and it should be worn promptly as conditions change.
The perceived temperature at the summit will hover around 15°C, but with drizzle and gusts up to 12 m/s, it will feel colder. While the risk of hypothermia is low, adequate protection against wetness and cold is crucial. There are no signs of thunderstorms, and the wind, though gusty, is not strong enough to impede movement significantly. Nevertheless, considering the potential for reduced visibility in the afternoon, an early start and timely descent are
However, the weather is expected to deteriorate in the afternoon. Light drizzle is forecast to begin around 3 PM, intensifying to a steady drizzle by 6 PM. This change will likely reduce visibility, significantly increasing the risk of getting lost in dense fog on the summit plateau. The boardwalks across the wetlands will become wet and slippery; therefore, strictly keep to the boardwalks and exercise extreme caution with your footing. Carrying full waterproof and breathable rain gear is essential, and it should be worn promptly as conditions change.
The perceived temperature at the summit will hover around 15°C, but with drizzle and gusts up to 12 m/s, it will feel colder. While the risk of hypothermia is low, adequate protection against wetness and cold is crucial. There are no signs of thunderstorms, and the wind, though gusty, is not strong enough to impede movement significantly. Nevertheless, considering the potential for reduced visibility in the afternoon, an early start and timely descent are
山岳ガイド — Mountain Guide
概要 Overview
新潟県と長野県の県境に位置する標高2,145mの百名山。山頂部に広がる「苗場(なえば)」と呼ばれる広大な高層湿原が独特の山容を生み出している、信越国境の名峰。
特徴・地形 Features
山頂台地は東西4km・南北約2kmの広大な湿原で、夏は池塘と湿原植物のお花畑が広がる。古来より神聖視され、修験道の対象とされてきた。
ベストシーズン Best Season
7月〜10月上旬。湿原のお花畑ピークは7月下旬〜8月。紅葉は10月初旬。
主要ルート Main Routes
祓川コース(最一般的・かぐら和田小屋)、小赤沢コース、ドラゴンドラ利用コース。
注意点・危険箇所 Cautions
山頂台地は道迷いリスクが高く濃霧時は要注意。湿原内の木道外への踏み込み禁止(植生保護)。
アクセス Access
上越新幹線越後湯沢駅から車・バス。祓川駐車場・小赤沢登山口へ。
※ 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。