Which Japanese Ski Areas Keep Their Snow at 4°C of Warming?

On 1 August 2026, two researchers published a number that is hard to read twice.

Nao Yoshizawa of Hokkaido University and Yuta Katsuyama of the Forest Research and Management Organization ran snow simulations across all 349 ski areas in Japan under three climate conditions. They asked one question: could each area run a stable season on natural snowfall alone, with no snowmaking.

	Fully operable	Partly operable
+2°C (reached 2030–2091)	53 of 349	108
+4°C (reached 2050–2111)	7 of 349	26

Seven. Published in Seppyo, the journal of the Japanese Society of Snow and Ice (DOI 10.5331/seppyo.88.4_295; Hokkaido University release). The method was a SNOWPACK snow model driven by d4PDF climate projections at 5 km resolution.

What the study does not say

It does not name the seven.

The paper reports that the survivors sit in high-latitude and high-elevation areas, and points at Hokkaido and Nagano. It stops there, and reasonably so — publishing a list of ski areas with a date on them is not a scientist’s job.

Updated on 8 October 2026. Japanese press coverage of the study (Alterna, via Yahoo! News Japan) gives the seven by region: three in Hokkaido, two in Tohoku and two on the Gunma–Nagano border. Our snowing-day temperatures agree on Hokkaido and on the Gunma–Nagano border, and not on Tohoku. Only 16 Japanese ski areas average −8 °C or colder on the days it snows; exactly three of them are in Hokkaido (Asahidake, Kurodake and Kiroro), and the coldest on Honshu is Shibutoge, at the top of Shiga Kogen on the Gunma–Nagano border, next to Yokoteyama. No Tohoku ski area reaches −8 °C; the coldest are Tengendai (−7.8 °C) and Gassan (−7.4 °C). These are our matches, not the paper’s list.

But we measure snowfall at 397 Japanese ski areas, and know the latitude and summit elevation of every one. So we can ask the question the paper leaves open: if latitude and elevation are what matter, which ski areas are on which side of the line?

The answer inverts the ranking this entire site is built on.

Japan’s snow is not where you would guess

Here are the eight snowiest prefectures with four or more ski areas, and Hokkaido.

Prefecture	Areas	Mean snowfall	Mean latitude	Mean summit	In world top 100
Niigata	48	554 cm	37.1°N	827 m	32
Toyama	4	410 cm	36.6°N	826 m	1
Ishikawa	4	391 cm	36.4°N	738 m	2
Yamagata	17	338 cm	38.2°N	811 m	2
Fukushima	24	325 cm	37.5°N	1,063 m	1
Iwate	11	303 cm	39.7°N	948 m	0
Akita	17	298 cm	39.7°N	500 m	0
Nagano	64	290 cm	36.4°N	1,554 m	8
Hokkaido	87	220 cm	43.4°N	398 m	0

Read the first and last rows together.

Hokkaido sits six degrees of latitude further north than Niigata and gets less than half the snow. Eighty-seven ski areas, and none of them makes the world’s top 100. Niigata has 48 areas and puts 32 in the top 100.

This surprises almost everyone, including people who have skied Japan for years, because Hokkaido is the name attached to Japanese powder abroad. Hokkaido’s snow is famously dry and cold. It is not famously deep, and the numbers say it is not deep at all by Japanese standards.

Japan’s snow is a Niigata phenomenon. And Niigata averages 37.1°N and 827 m.

Why that is the bad news

Latitude and elevation are not arbitrary criteria. They are proxies for one thing: how far the air temperature sits below freezing.

Japan’s extraordinary snowfall comes from a mechanism that has nothing to do with either. Cold air leaves Siberia, crosses the Sea of Japan, picks up moisture over a few hundred kilometres of warm water, hits the mountains of Honshu and unloads. It works at low elevation and at the latitude of Athens because the air is cold, not because the ground is high.

That is exactly what makes it fragile. Sea-effect snow near the coast falls close to the freezing line already, and how much room each range has before its snow turns to rain is something we have measured against the Alps and the Rockies. Raise the temperature and it does not fall as less snow — it falls as rain, and a season’s base disappears rather than shrinks.

High ground and high latitude do not produce the snow. They protect it.

Nagano is protected by elevation — 1,554 m mean summit, the highest of any prefecture here. Hokkaido is protected by latitude — 43.4°N. Niigata has neither. It has the sea.

The ranking’s top 20 is the exposed group

Applying the study’s own criteria — below 38°N and below 1,200 m at the summit — to the 20 snowiest ski areas in Japan:

World rank	Ski area	Prefecture	Latitude	Summit	Snowfall
2	Okutadami Maruyama	Niigata	37.2°N	1,160 m	765 cm
5	Muikamachi Hakkaisan	Niigata	37.1°N	1,138 m	728 cm
=6	Iwappara	Niigata	36.9°N	954 m	712 cm
=6	Yuzawa Nakazato	Niigata	36.9°N	801 m	712 cm
=6	Nakazato Snow Wood	Niigata	36.9°N	712 m	712 cm
=6	Yuzawa Park	Niigata	36.9°N	644 m	712 cm
11	Itoigawa Seaside Valley	Niigata	36.9°N	581 m	703 cm
=12	Ishiuchi Maruyama	Niigata	37.0°N	912 m	695 cm
=12	Joetsu International	Niigata	37.0°N	896 m	695 cm
=12	Maiko Snow Resort	Niigata	37.0°N	687 m	695 cm
=12	Ippon Sugi	Niigata	36.9°N	436 m	695 cm
=12	Ishiuchi Hanaoka	Niigata	37.0°N	342 m	695 cm
18	Charmant Hiuchi	Niigata	37.0°N	998 m	690 cm
19	Seki Onsen	Niigata	36.9°N	1,139 m	689 cm
20	Tateyama Sanroku	Toyama	36.6°N	1,112 m	682 cm
=21	Hakuba Iwatake	Nagano	36.7°N	1,150 m	668 cm
24	ARAI Snow Resort	Niigata	37.0°N	1,147 m	663 cm

Seventeen of the top 20 fail both criteria — every area above. Japan’s snowiest ski area, Okutadami Maruyama, is one of the seventeen. Several summits sit below 700 m; one is at 342 m, which is lower than the base of most resorts in the Alps.

The three that clear the bar are Hakuba 47 and Tsugaike Kogen on elevation, and Mount Gassan on latitude. Gassan is the genuine outlier: it is buried so deep that it opens in April and runs into July, which is how it reaches 25th in the world without anyone skiing it in January.

A site that ranks ski areas by snowfall, as this one does, is largely ranking the group with the least protection.

What is likely to still be there

Two profiles clear the bar. These are our inference from our data, not the paper’s list.

Protected by elevation — Nagano’s high terrain

Ski area	Summit	Snowfall	World rank
Hakuba 47	1,651 m	668 cm	=21
Tsugaike Kogen	1,602 m	668 cm	=21
Kagura	1,845 m*	565 cm	55
Kagura Area	1,849 m	542 cm	69
Hakuba Happo-One	1,722 m	414 cm	=155

Kagura has no survey figure for its summit; 1,845 m is the resort’s own.

Hakuba is the interesting case. It is high enough to be in the protected group and snowy enough to be worth the trip — the clearest case in Japan of both.

Kagura is the one Niigata name here, and it is the exception that confirms the rule: it is the highest lift-served terrain in the prefecture. Everything else Niigata is famous for sits far below it.

Protected by latitude — Hokkaido’s volcanic high ground

Ski area	Latitude	Summit	Snowfall	World rank
Daisetsuzan Sounkyo Kurodake	43.7°N	1,544 m	396 cm	=178
Asahidake	43.7°N	1,609 m	388 cm	=194
Kiroro	43.1°N	1,095 m	331 cm	=351
Sapporo Kokusai	43.1°N	1,055 m	331 cm	=351

These rank between 178th and 351st in the world today. On present snowfall they are unremarkable by Japanese standards. On the study’s criteria they are among the safest places in the country.

What this actually means for a trip

It does not mean go now or never. The +2°C window in this study opens in 2030 at the earliest and the +4°C window in 2050. Nobody planning next February is affected.

It does mean the received wisdom is about to age badly. “Go to Niigata for the deepest snow” is correct today and is the advice most exposed to being wrong within a career.

If you are choosing between Niseko and Hakuba and expect to keep coming back for twenty years, Hakuba’s elevation is a real argument that snowfall alone does not capture.

If you want to ski Japan’s genuinely deepest snow, the argument for going sooner is stronger than for anywhere else, not because it vanishes next year, but because Okutadami Maruyama at 1,160 m is not a place that can be replaced by building higher.

Where we could be wrong

We do not have temperature projections. Our figures are snowfall over the last twelve winters. We do record the temperature on the days it snowed, and compare that headroom across ranges, but that describes today’s climate, not a warmer one. Latitude and elevation are proxies for the temperature margin, and they are the proxies the study itself points to, but a proxy is not the measurement. Two areas at the same latitude and height can differ in ways this cannot see.

The seven are not necessarily on our lists. We are applying the paper’s stated direction to our own data. The paper ran a snow model on each site; we did not. If our lists and their seven disagree, theirs is the one to believe.

Snowmaking is excluded from all of it. The study is explicit that it models natural snow only. Many of these areas make snow, and a resort that survives on machines is still a resort. What disappears in this scenario is the powder, not necessarily the business.

A partly operable season is still a season. At +4°C the study also counts 26 partly operable areas. A shorter season at Hakuba is a different thing from Hakuba closing.

How this was measured

Our snowfall figures are daily snowfall summed over each of the twelve winters from 2014/15 to 2025/26 and averaged per season, winter defined per hemisphere. Source is Open-Meteo historical data from the ERA5 reanalysis.

Our snowfall figures are modelled, run low and describe the last twelve winters only; every projection in this article is the paper’s, not ours. How we check the model →

Grid elevation is not slope elevation either, which is why nearby resorts return identical figures and appear here as ties.

Summit elevations are from the Geospatial Information Authority of Japan. The climate study’s figures, method and scenario dates are from the published paper and the university’s release, both linked above; the ski-area-level analysis is ours and the authors are not responsible for it.