Japan's Snowiest Ski Areas Rain on Two Winter Days in Five

This site ranks 3,065 ski areas by how much snow falls on them. Nine of the world’s top ten are Japanese, and Okutadami Maruyama in Niigata is first.

That ranking answers one question and quietly implies an answer to a different one. How much falls is not the same as what falls. A wet metre at 0°C and a dry 50 cm at −10°C are both “snow”, and only one of them is why people fly to Japan.

So we measured the second thing separately. The two do not turn out to be opposites — across all 393 Japanese ski areas the rank correlation is 0.61, which says that snowier places do tend to have better snow. What breaks is the top of each list.

Of the 20 snowiest, the median quality rank is 183rd.
Of the 20 highest quality, the median snowfall rank is 233rd.

The middle of the two rankings agrees. The extremes swap places, and the extremes are what everybody books.

What we measured

Four things, from the same ERA5 reanalysis, over the same three winters, for every Japanese ski area:

		Why
Dryness	Mean air temperature on days it snowed	Colder snow is less dense. This is the main ingredient of what people mean by quality
Frequency	Share of winter days with 5 cm or more	How often you get a fresh surface, rather than one big storm and three clear weeks
Rain penalty	Share of winter days with 1 mm or more of rain	Rain collapses the surface, and refreezes as a crust
Wind penalty	Mean daily maximum wind on snowing days	Wind strips faces and builds slab

Combined by multiplication, not addition: dryness × frequency, then reduced by the two penalties. A place that is bitterly cold but rarely snows is not good. Neither is a place that snows every day at 0°C. Adding them would let one good column carry a bad one.

How much snow falls is not an input. Including it would just reproduce the snowfall ranking under a new name. The value is in where the two part company.

The disagreement

These are the resorts our own snowfall ranking puts near the top of the world, with what the quality measure says about them.

	Snowfall rank	Quality rank	Temp when snowing	Rain days	Days over 5 cm
Itoigawa Seaside Valley	13	285	+0.1°C	31%	37%
Tainai	17	252	−0.7°C	45%	40%
Ishiuchi Hanaoka	19	266	−0.3°C	41%	36%
Ippon Sugi	19	250	−0.5°C	41%	36%
Maiko Snow Resort	19	227	−0.9°C	41%	36%
Yuzawa Park	5	236	−0.7°C	27%	44%
Nakazato Snow Wood	5	215	−1.1°C	27%	44%
Okutadami Maruyama	1	69	−3.5°C	20%	45%

Tainai is 34rd in the world for snowfall and it rains there on 45% of winter days. Itoigawa Seaside Valley, 13th, averages above freezing on the days it snows.

Okutadami is the exception that makes the pattern legible. It is first in the world for volume and still reaches 69th for quality, because at a 1,160 m summit it is the highest of the Niigata heavyweights, cold enough to average −3.5°C when snowing, and it clears 5 cm on 45% of winter days. It is not in the top ten for quality, but it is nowhere near the bottom either. Elevation is what separates it from Itoigawa Seaside Valley, 581 m and 281st.

None of this makes the volume figures wrong. Seven metres really does fall on Tainai. It just does not all fall as the thing people picture.

What comes out on top instead

Ordered by quality, taking one entry per valley so that the ten Shiga Kogen areas do not fill the table:

	Quality rank	Snowfall rank	Temp when snowing	Rain days
Daisetsuzan Sounkyo Kurodake	1	235	−11.0°C	3%
Asahidake	2	308	−11.6°C	4%
Chisennupri	3	150	−7.3°C	7%
Shiga Kogen Shibutoge	4	322	−11.3°C	8%
Togakushi	6	39	−5.3°C	11%
Kawaba	7	116	−7.2°C	11%
Tengendai Kogen	9	140	−7.8°C	12%
Tambara	10	116	−6.8°C	11%
Kagura	11	58	−6.7°C	15%

The top two are volcanic high ground in central Hokkaido, ranked 235th and 308th for volume. Kurodake sees rain on three winter days in a hundred; Tainai on forty-five.

Kagura is the closest thing to a resort that wins both columns — 58th for volume, 11th for quality, and it is Niigata’s highest lift-served terrain, which is the whole explanation.

The famous names

	Quality rank	Snowfall rank	Temp when snowing	Rain days
Kiroro	24	312	−8.0°C	6%
Appi Kogen	33	157	−5.2°C	10%
Niseko Grand Hirafu	38	416	−6.2°C	7%
Zao Onsen	78	503	−6.2°C	13%
Shiga Kogen (base area)	75	722	−6.5°C	10%
Hakuba Happo-One	102	112	−4.1°C	22%
Furano	115	915	−7.6°C	8%
Rusutsu	125	1,095	−6.1°C	8%
Nozawa Onsen	133	66	−4.0°C	37%

Niseko is 416th for volume and 38th for quality, which is a fair description of its reputation: not the deepest in Japan, but cold and consistent.

Nozawa rains on 37% of winter days and Hakuba on 22%. Both are excellent places to ski and both sit low on the Honshu side, where midwinter regularly arrives as rain. That is not a criticism of either; it is the reason a January booking there carries more risk than the same week in Hokkaido.

Where the quality actually is, by region

Prefecture	Median quality score
Iwate	18.9
Gunma	15.8
Fukushima	14.6
Nagano	11.9
Hokkaido	9.8
Niigata	8.6
Yamagata	7.8
Gifu	6.2
Hiroshima	1.8

Hokkaido is not top of this table, and that surprised us. Its snow is cold — that part holds, but many Hokkaido ski areas are small and low, and they get frequent light snowfall rather than frequent 5 cm days. Rusutsu clears 5 cm on 10% of winter days and Furano on 9%, against 26% at Tambara in Gunma.

So the honest reading is that Hokkaido has the coldest snow and the least rain, while inland Honshu at altitude has the most frequent meaningful snowfall, and the top of the ranking is where both happen at once — the Daisetsuzan volcanoes, Shibutoge at 2,167 m, Tengendai at 1,860 m.

Where this is weak, in detail

The weights are our judgement, not a measurement. Nothing in the physics says dryness should be scaled to zero at +2°C and full at −12°C, or that rain should cost at most 65%. We chose those. Reasonable people would choose differently and the order would shift. What the numbers can carry is that every ski area went through the identical calculation.

Rain and frequency only resolve to a valley. All ten Shiga Kogen areas return the same 20% powder-day share and 8% rain-day share, because the reanalysis grid does not separate precipitation within a valley. Temperature does resolve — Shibutoge reads −11.3°C against −6.5°C at the base area, so the ranking separates them, but on the precipitation columns they are one place, not ten.

Three winters. Same limitation as everything else here. 2023/24 through 2025/26.

This measures the climate, not the day. A resort with a mediocre score still has extraordinary days. The Powder Score on each resort page is the one that answers “what about right now”.

And it is Japan only for the moment. Applying this worldwide needs the elevation of every ski area, and we hold that for 824 of 3,065 — mostly the Japanese ones. That is a gap in our data, not in what is knowable.

How this was measured

Daily values from Open-Meteo historical data, ERA5 reanalysis, December to March across the last three completed seasons. Temperature is corrected to each ski area’s mid-elevation using a standard 6.5°C/km lapse rate, which changes the median resort by 0.2°C — small, because the source data already resolves elevation closely, and kept only because it matters for ski areas spanning large vertical.

Snowfall volume figures quoted for comparison come from the same source and carry the caveat they always do: ERA5 runs far below what resorts report, so the ranking is the meaningful part rather than the centimetre figure.