First snowfall and first snowcap records

First snowcap in the current cold-season year (JMA announcements)

As of retrieval at August 17, 2026, 21:00, no first snowcap date has been announced for the current cold-season year (the year that began in August 2026). This section only transcribes announced values. In past records, the mountain with the earliest median date was Mt. Asahi (Asahikawa) on September 23 and the one with the latest was Mt. Wanitsuka (Miyazaki) on January 15; see the chart and tables below.

Past first snowcap dates at 44 mountains nationwide (through the 2026 cold-season year)

These are records of visual observation (frozen at the 2026 cold-season year). Each line spans the earliest to the latest recorded date for the mountain, and the dot is the median date when the records are sorted from earliest. A cold-season year runs from August of the previous year through July, so the horizontal axis starts in August.

How observation works and how it changed

Even for records of the same phenomenon, the way observations are made has changed over time. Snow observation was switched from visual observation to automatic observation by instruments on February 3, 2020. The observation table of the Saga Local Meteorological Office, for example, states that the switch took place at 15:00 that day, that the normal for first snowfall is visual observation data adjusted to values equivalent to automatic observation, and that the records for the earliest and latest dates had their statistics cut off on that day and counted anew.

The same observation table also states that visual observation and reporting of first frost and first ice ended starting with the 2026 cold-season year. Snow continues to be observed automatically, and the first snowfall values at staffed weather stations are published by local meteorological offices.

For first snowcap on mountains as well, visual observation continued only through the 2026 cold-season year, which has since ended. That is why the dates on this page stop at that cold-season year (as of August 17, 2026). From the current cold-season year (the year-long period that began in August 2026), snow conditions on summits based on analyzed snow depth are to be shown with hourly updates, and the official explanation adds, "Please note that the methods differ and the values cannot be compared directly."

For that reason, the list on this page closes with records from visual observation only. We do not append values from after the change of method; we keep only dates counted the same way.

Source of the definitions: JMA, Terms used in weather forecasts: seasonal phenomena (in Japanese, accessed August 17, 2026). Source of the records: JMA, First snowcap records and related data (retrieved August 17, 2026).