Fetching the forecast…
Shows the Japan Meteorological Agency’s published forecast as-is: today, tomorrow and the day after with rain probability, plus the seven-day outlook. Your region is remembered.
This tool fetches forecasts directly from the Japan Meteorological Agency (www.jma.go.jp). All that is sent is which region you looked at, and it does not pass through this site’s server. Your chosen region is stored in the browser only.
Questions
Where does the data come from?
JMA’s published JSON, read directly by your browser. It does not pass through this site, and nothing is altered.
Does anyone learn which region I picked?
JMA’s servers see which region’s file was requested. Nobody else does, and the remembered choice stays in your browser.
Does it show warnings?
No — forecasts only. For warnings and evacuation guidance, consult JMA or your local authority directly.
When is the forecast updated?
JMA issues the prefectural forecast three times a day, at 05:00, 11:00 and 17:00, and the weekly outlook at 11:00 and 17:00. Extra updates go out when the picture changes substantially. This page reads the current file when you open it, so reopening after an issue time shows the new one.
A weather app disagrees with this.
Different sources. This displays the forecast exactly as JMA issued it; most apps blend their own model output, often including non-Japanese models, and pick locations differently. Neither is simply right — this is the one to check when you want the official position.
Can I see past weather?
No. The files read here are forecasts only and carry no observation record. For historical temperature and rainfall, use the past-data search published by JMA.