UTC Offset
UTC+09:00
Seirō, Japan Snapshot 2026
Where is Seirō?
Seirō, Japan
- Continent
- Asia
- Country
- Japan
- City
- Seirō
- Population
- 14.3K
- Coordinates
- 37.98°, 139.25°
Seirō is a city in Japan with a population of approximately 14.3K. Average temperatures range from -1°C (30°F) in January to 30°C (85°F) in August. The best time to visit is May, June, September, October.
Time in Seirō right now
Open full time & time zone page 21:50 50
Tuesday, June 30, 2026
IANA time zone
Asia/Tokyo
Daylight saving
No DST
Next DST change
—
Live weather in Seirō
Daylight in Seirō today
View full sunrise & sunset page Sunrise
Sunset
Day length
14h 46m
Climate normals for Seirō
Long-term monthly averages based on historical data.
January
Wet 
February
Wet March
Wet April
Fair May best
Excellent June best
Excellent July
Wet August
Wet September best
Excellent October best
Good November
Wet December
Wet | Month | Temp | Feels Like | Rain | Sun | Humidity | UV | Status | Details |
|---|---|---|---|---|---|---|---|---|
| January | 4°C / -1°C | -1°C / -6°C | 27days (237 mm) Wet | 5.8h Fair | 82% Humid | 2.5 Moderate | Wet | View Details |
| February | 4°C / -1°C | 0°C / -6°C | 22days (161 mm) Wet | 7.4h Good | 79% Humid | 3.5 Moderate | Wet | View Details |
| March | 10°C / 2°C | 7°C / -2°C | 18days (136 mm) Wet | 8.1h Good | 76% Humid | 4.6 Moderate | Wet | View Details |
| April | 16°C / 7°C | 14°C / 4°C | 15days (132 mm) Wet | 9.2h Good | 76% Humid | 5.7 High | Fair | View Details |
| May best | 21°C / 12°C | 22°C / 11°C | 14days (134 mm) Wet | 9.5h Good | 77% Humid | 5.7 High | Excellent | View Details |
| June best | 24°C / 17°C | 27°C / 18°C | 15days (160 mm) Wet | 9.6h Good | 82% Humid | 6.6 High | Excellent | View Details |
| July | 28°C / 22°C | 33°C / 25°C | 18days (256 mm) Wet | 9.5h Good | 84% Humid | 6.9 High | Wet | View Details |
| August | 30°C / 23°C | 35°C / 27°C | 18days (238 mm) Wet | 9.9h Good | 83% Humid | 7 High | Wet | View Details |
| September best | 26°C / 19°C | 29°C / 21°C | 16days (193 mm) Wet | 8.1h Good | 82% Humid | 5.6 High | Excellent | View Details |
| October best | 19°C / 13°C | 19°C / 11°C | 15days (171 mm) Wet | 7.1h Good | 80% Humid | 4 Moderate | Good | View Details |
| November | 13°C / 7°C | 11°C / 4°C | 20days (191 mm) Wet | 6.8h Fair | 79% Humid | 2.8 Moderate | Wet | View Details |
| December | 7°C / 2°C | 3°C / -3°C | 27days (277 mm) Wet | 5.6h Fair | 83% Humid | 1.8 Low | Wet | View Details |
Monthly Temperatures
High Low
Line chart showing monthly temperatures. Jan: 4°C / -1°C . Feb: 4°C / -1°C . Mar: 10°C / 2°C . Apr: 16°C / 7°C . May: 21°C / 12°C . Jun: 24°C / 17°C . Jul: 28°C / 22°C . Aug: 30°C / 23°C . Sep: 26°C / 19°C . Oct: 19°C / 13°C . Nov: 13°C / 7°C . Dec: 7°C / 2°C .
Monthly Rainfall
Rainfall
Bar chart showing monthly rainfall. Jan: 237 mm. Feb: 161 mm. Mar: 136 mm. Apr: 132 mm. May: 134 mm. Jun: 160 mm. Jul: 256 mm. Aug: 238 mm. Sep: 193 mm. Oct: 171 mm. Nov: 191 mm. Dec: 277 mm.
Monthly Humidity
Humidity
Line chart showing monthly humidity. Jan: 82%. Feb: 79%. Mar: 76%. Apr: 76%. May: 77%. Jun: 82%. Jul: 84%. Aug: 83%. Sep: 82%. Oct: 80%. Nov: 79%. Dec: 83%.
Monthly Wind Speed
Wind Speed Gusts
Bar chart showing monthly wind speed. Jan: 22 km/h . Feb: 21 km/h . Mar: 19 km/h . Apr: 18 km/h . May: 16 km/h . Jun: 14 km/h . Jul: 13 km/h . Aug: 14 km/h . Sep: 15 km/h . Oct: 17 km/h . Nov: 19 km/h . Dec: 22 km/h .
Sea Temperature
Sea Temperature swim
Line chart showing monthly sea temperature. Jan: 11°C . Feb: 10°C . Mar: 10°C . Apr: 12°C . May: 16°C . Jun: 21°C . Jul: 26°C . Aug: 29°C . Sep: 28°C . Oct: 23°C . Nov: 18°C . Dec: 14°C .
UV Index
UV Index
Bar chart showing monthly UV index. Jan: UV 3. Feb: UV 4. Mar: UV 5. Apr: UV 6. May: UV 6. Jun: UV 7. Jul: UV 7. Aug: UV 7. Sep: UV 6. Oct: UV 4. Nov: UV 3. Dec: UV 2.
Frequently Asked Questions
Seirō has a population of approximately 14.3K.
The best months to visit Seirō are May, June, September, October, when temperatures are pleasant and rainfall is lower.
Seirō receives approximately 2286mm of rainfall annually across 225 rainy days.
Seirō is located in Japan, in the Asia region.