ニュース
El Niño Record +4.0°C: What It Means for Japan Snow This Winter
The Japan Meteorological Agency (JMA) released its El Niño Monitoring Report on October 9. The El Niño event that began in spring 2026 reached its strongest level on record in September, and it is expected to stay that strong through winter. This is the most recent official input for judging this winter's snow.
September's sea surface temperature was the highest on record
According to Japan Weather Association's tenki.jp and other outlets reporting on the JMA bulletin, sea surface temperatures in the El Niño monitoring region were 4.0°C above the reference value in September. That tops the previous high of 3.6°C in December 1997, the highest since records began in 1949, and makes it the largest for any month.
JMA puts the probability that an event of record strength continues into winter at 100%. Weathernews reports that it could peak around November to December.
- Released: October 9 (JMA)
- September sea surface temperature vs. reference value: +4.0°C
- Previous record: +3.6°C in December 1997
- Probability of continuing into winter: 100%
What it means for this winter's snow
Japan tends to have a warmer winter during El Niño events. According to tenki.jp, this winter is expected to be mild nationwide, with snowfall on the Sea of Japan side (the western coast of Honshu and Hokkaido, where most of the country's powder falls) below normal. However, cold air outbreaks are expected to arrive repeatedly, and some areas could still see heavy local snowfall.
Because the winter pressure pattern (high to the west, low to the east, which drives snow onto the Sea of Japan side) is less likely to last, low-pressure systems passing along Japan's south coast may come through more often. One commentary says this calls for attention to snow even on the Pacific side, where snow is normally scarce. Another, from Weathermap, mentions the possibility of heavy snow in the Kanto region around Tokyo.
For Hokkaido, the Sapporo Regional Headquarters of JMA issued its cold-season outlook in September. tenki.jp reports that snowfall on the Sea of Japan side is forecast to be normal or below normal from December to February, with the possibility of sudden heavy snow early in the season.
How skiers and snowboarders can read the outlook
A below-normal snowfall outlook describes the season as a whole. JMA's outlook does not rule out a few days of strong cold air bringing a good amount of snow. If you are chasing powder, it is more practical to watch short-range cold snap forecasts and each resort's snow depth than to rely on the seasonal outlook alone.
- Opening dates for the new season are updated every morning on the opening information page.
- Check conditions on the mountain at Niseko with the Niseko Grand Hirafu live cam.
- For the Hakuba area, see the Hakuba Happo-One live cam.
The next bulletin is due around the 10th of each month. We will check whether the November update changes the outlook for the peak.
Sources
- JMA: El Niño/La Niña (El Niño Monitoring Report, latest issue updated October 9, Reiwa 8)
- El Niño is the strongest on record and expected to continue into winter: monitoring report released October 9 (Japan Weather Association tenki.jp)
- El Niño reaches record strength, with a possible peak in November to December (Weathernews)
- Record strength to continue into winter: mild winter expected nationwide, but heavy snow possible in Kanto (Weathermap)
- Hokkaido: warmer than normal into winter, with less snow overall but possible pinpoint heavy snowfall? (tenki.jp)
Prepared with AI assistance from public sources. Always check each resort's official website for the latest information.