Data notes

Source, method and limits

This site compares published climate normals. It is not an official Japan Meteorological Agency product and it does not provide a weather forecast.

Source and attribution

Displayed values are transcribed and organized from the Japan Meteorological Agency (JMA), Tables of Climatological Normals (1991–2020). They are presented here in an independently designed comparison interface.

Based on information published by the Japan Meteorological Agency. JMA website content is generally available under the Public Data License (Version 1.0) unless a specific rights notice applies; source citation is required. See the JMA website terms of use.

What a climate normal means

Climate normals summarize historical observations over a standard 30-year period. The figures in this release use the 1991–2020 period. They help compare broad seasonal patterns; they cannot predict conditions on a particular day or trip.

How to use this reference

Use the comparison to understand differences between the five displayed observatories.
Check official forecasts and local guidance near departure for current conditions and disruptions.
Do not treat a monthly average, total or sunshine figure as a guarantee of comfort, safety or travel suitability.

Scope

The first release covers Sapporo, Tokyo, Osaka, Fukuoka and Naha. City labels refer to the relevant JMA observatory data, not every neighborhood within a metropolitan area.