Table　Mean monthly air temperature (MMAT :℃ )，monthly maximum air temperature(MAXAT :℃ )，monthly minimum air temperature (MINAT :℃) and monthly precipitation(MP :mm)

*1 Hakuun hut　Alt.1,995m N43:39 E142:55 Air temperature data at Hakuun hut in Daisetsu Mountains, central Hokkaido in 1990-1993 Toshio Sone http://hdl.handle.net/2115/18796

*2 Mt.Maehurano　Alt.746m N43:23 E142:34 Japan Meteorological Agency 1976～2005

*3 Biei　Alt.250m N43:35 E142:30 Japan Meteorological Agency 1980～2010

*4 Asahikawa　Alt.120m N43:45 E142:22 Japan Meteorological Agency 1980～2010

At Daisetsuzan, autumn foliage reaches its peak in September, and snow starts to fall and pile up from October. The long winter season continues until June, when the accumulated snow finally starts to melt.

In general, air temperature drops by 0.6℃ with every 100 m climb in elevation, and drops by 0.6～0.7℃ for every degree of latitude travelled northward from the equator. The apparent temperature felt by the human body is also said to drop by 1℃ for every 1 m/s increase in wind speed. Thus, in a 2,000-meter class mountain with a wind speed of 5 m/s, humans will feel a temperature 17℃ lower than that at the foot of the mountain. The body’s temperature will further decrease through evaporation in case it is wet from sweat or rain. As a matter of fact, there have been cases of death by hypothermia at Daisetsuzan during the summer.

With plenty of swamps and snow patches covering the trails at Daisetsuzan, it is easy to get lost especially when there is fog. Hikers should be thoroughly prepared with the proper skills and equipment, and should always pay attention to guide posts and tracks on the trails.

In this page, spring refers to the month of June, summer refers to July to August, autumn refers to September, and winter refers to October to May.

Spring (June)

While the accumulated snow is already starting to melt, it is not uncommon for snow to fall even at this time. At the tops of the mountains, thick snow still covers the ground. Most of the roads that have been closed during winter begin to re-open.

• Hokkaido Route 223 (Aizankei–Kamikawa)                 opens early May

  Hokkaido Route 966 (Tokachidake Onsen–Biei)         opens late April

  Hokkaido Route 1162 (Ginsendai access road)            opens late June

  Kamikawa Town Kogen Onsen access road                  opens early June

Road Information in Hokkaido       https://info-road.hdb.hkd.mlit.go.jp/en/

Summer (July to August)

Overview

The best time to go hiking in the alpine zone of Daisetsuzan to enjoy the summer scenery is from mid-July to late August. The alpine zone in Daisetsuzan generally refers to the area beyond the Sugatami Pond (at the top of the ropeway from Asahidake Onsen), the area beyond the ropeway and chair lift from Sounkyo Onsen, and the mountain trail going up from Tokachidake Onsen.

For a more in depth look at hiking in Daisetsuzan, you can check out the “Hiking in Daisetsuzan National Park” feature in Lonely Planet Japan (p. 601, 14th edition, published Sep 2015) or the “Tracks and Walks” section of the “ASAHI-DAKE The heart of the Daisetsuzan National Park” 1:25,000 hiking map.

From mid-July, the snow cover starts to recede from the mountain slopes, and disappears completely from the trails. From the ridge trails, you can enjoy a commanding view of the surrounding peaks. As the snow melts, alpine plants start to grow, blooming into vast flower fields that attract rare alpine butterflies. Small mountain mammals like pikas and chipmunks also start to come out.

The Ainu people called this place Kamui Mintara or “playground of the gods”, a fitting name for the truly majestic landscapes you can see in the summertime.

Nevertheless, hikers in Daisetsuzan should keep in mind that the environment in the alpine zone can be harsh, and that hiking here is not a walk in the park. To help avoid accidents, it is important to take note of the following points.

Temperature

The alpine zone of Daisetsuzan experiences low temperatures even during July and August. It can be quite cold even in the daytime when the sun is hidden and the wind is blowing. You should always be prepared with cold weather clothing. Short pants and short-sleeved shirts are out of the question.

Fog

Fog can be one of the greatest dangers in Daisetsuzan. It can be difficult to navigate through thick fog in flat areas near the peaks, and even seasoned climbers can easily lose their way. It is especially important to be careful on trails with swamps and snow patches. In case you get lost, you should stay calm and not panic. Wait for the fog to lift, or try to go back with extreme caution.

Rain

Rain falls frequently at Daisetsuzan in summer. It can be quite cold when you get wet from the rain, especially if the wind is blowing. There have been incidents of death by hypothermia at Daisetsuzan during the summer. When rain falls, fog can also form, so you should be careful not to lose your way. Always be prepared with rain gear, and immediately take shelter in a mountain hut or your tent in case of heavy rain.

Wind

Strong winds can occur in the mountain peaks and ridges, even when there is little or no wind at the foot or the campsites and mountain shelters. When the wind blows in Daisetsuzan, it can feel extremely cold, especially when the sun is hidden, and there is a danger of losing body heat very rapidly in windy and rainy weather. Strong winds can also blow away tents, so it is important to make sure that they are firmly secured.

Whatever the conditions, when you go summer hiking in Daisetsuzan, you should always be prepared with the proper supplies and equipment, including rain gear, warm clothing, hiking shoes or boots that can be used on the snow, and sufficient food and water. Keep in mind that in early July, snow still remains in the alpine zone, and patches of snow may still cover parts of the trail. From the middle to the end of August, autumn starts to arrive at the mountain peaks, and light snowfall is not an uncommon occurrence.

Flower Fields in Daisetsuzan >

Daisetsuzan Grade System >

The Daisetsuzan Grand Traverse >

Autumn (September)

Overview

Autumn arrives in Daisetsuzan in September, and brings the earliest colored leaves in all of Japan. It begins from the mountain tops and gradually makes it way to the foot, covering the slopes in vivid colors, with the reds of the Japanese rowans and the yellows of the Erman’s birch trees, mixed with the greens of the dwarf pines and other conifers. Even small alpine shrubs like Aleutian avens show autumn colors, making hikes in this season a feast for the eyes. The colored leaves can usually be enjoyed from mid to late September, though the exact timing and the brightness of the colors vary slightly from year to year.

At the mountain tops, snow starts to fall from around mid-September, and can pile up knee-deep by the end of the month. If you are doing a hike during this season, you should be prepared with the proper equipment for snow and cold weather.

This season also sees a large influx of visitors from in and out of Japan looking to enjoy the autumn colors. To help preserve the nature and prevent accidents, some access roads are closed to regular traffic during this time.

Private Car Restriction Information >

Winter (October to May)

Overview

Compared to the lowland climate, autumn comes early and spring comes late in Daisetsuzan. Winter extends for almost 8 months, with the snow starting to fall in earnest from October, severe winter conditions lasting from November to April, and the snow remaining on the trails and roads until the end of May. During this season, the mountains experience extreme cold temperatures and strong winds, so if you are planning to do winter hiking or winter sports, you need to have the proper knowledge, skills, and equipment, as well as good judgment with regards to the weather.

In the areas at the base of the mountains, various winter events are held from December to March. You can enjoy festivals held on frozen lakes, or experience different activities and attractions that make use of the snow and ice.

Whenever you plan to visit an event or go hiking in Daisetsuzan during the winter, always check in advance the weather forecast, including information about avalanches and road closures. If you are driving, make sure to drive carefully, keeping in mind proper driving techniques on winter roads.

Driving safely on winter roads >

Parking Manners

Always park your car in designated parking areas. Parking on the side of the road is prohibited, as this may obstruct traffic and snow removal operations.

Backcountry avalanche information >

 
Transportation Access >

Mountain guides >