Summit Weather Japan: YAMAYOMI

YAMAYOMI rates the summit weather of 1,059 Japanese peaks, including all 100 Famous Mountains (Hyakumeizan), so you can pick the right day and the right mountain in 30 seconds. Free, no account.

SUMMIT CONDITIONS, NOT VALLEY WEATHER
Every forecast is corrected to summit elevation. Gusts, precipitation, lightning, hypothermia risk and visibility are combined into a 5-level climbing score. Daily ratings use the harshest hour of the walking window (6:00-15:00), so the score errs on the safe side.

MAP FIRST
Peaks appear as color-coded pins on a nationwide map. See at a glance which mountains look good this week. Switch layers between score, temperature and wind.

7-DAY OUTLOOK
Each peak shows daily scores for the next 7 days, with gusts, precipitation and the summit's low temperature.

ASK "WHEN SHOULD I GO?"
Pick a mountain and get a plain-language answer about which day looks best and why (wind, rain, temperature). Compare several peaks side by side.

1,059 PEAKS
Based on the Geospatial Information Authority of Japan's list of major mountains. All 100 Famous Mountains are included.

PRIVACY
No ads, no account, no location tracking. Usage statistics can be turned off in Settings at any time.

NOTE
Ratings are estimates from weather models and may differ from actual conditions. Trail status, snowpack and hut information are not included. The final decision is yours.

Mountain data: Geospatial Information Authority of Japan. Forecast: Open-Meteo.