Monthly average of daily maximum UV index · JMA ground observation data · Tsukuba (nearest official station to Tokyo)
10-yr avg (2015–2024)
6.0
High
10-yr range
5.6–6.6
year to year
May 2025
5.0
Moderate
Peak (clear day noon)
8–9
Very High
0–2 Low
3–5 Moderate
6–7 High
8–10 Very High
11+ Extreme
A typical May day in Tokyo averages UV 6.0 (High) — sun protection is needed. On clear sunny days, UV at solar noon regularly reaches Very High (8–9). SPF 50+ sunscreen, UV-blocking sunglasses and a hat are recommended whenever you are outdoors for extended periods. Check the Japan Meteorological Agency for current conditions before your trip:
Historical data: Japan Meteorological Agency (JMA) · Ground observation · Tsukuba station (36.06°N 140.13°E) · Monthly average of daily maximum UV index · 2015–2024. Tsukuba is the nearest JMA UV observation station to central Tokyo (~60 km north).