September weather forecastRoppongi, Japan
September
Weather in September
September, the first month of the autumn in Roppongi, is also a moderately hot month, with an average temperature varying between 21.5°C (70.7°F) and 26.9°C (80.4°F).Temperature
The arrival of September correlates with a minor temperature reduction, down from August's hot 30.6°C (87.1°F) to a moderately hot 26.9°C (80.4°F). During the month of September, the nighttime temperature falls to an average of 21.5°C (70.7°F).Humidity
In Roppongi, the average relative humidity in September is 74%.Rainfall
September is the month with the most rainfall. Rain falls for 12.9 days and accumulates 54mm (2.13") of precipitation.Snowfall
March through December are months without snowfall in Roppongi.Daylight
In September, the average length of the day is 12h and 25min.On the first day of the month, sunrise is at 05:13 and sunset at 18:08. On the last day of September, in Roppongi, Japan, sunrise is at 05:35 and sunset at 17:26 JST.
Sunshine
In September, the average sunshine in Roppongi is 7.8h.UV index
In Roppongi, the average daily maximum UV index in September is 6. A UV Index value of 6 to 7 symbolizes a high health vulnerability from exposure to the Sun's UV radiation for average individuals.Note: In September, the maximum UV index of 6 transforms into these recommendations:
Deflect overexposure. Sun protection is a necessity. Stay in the shade and limit direct sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its strongest. Remember, however, that not all shade structures provide full sun protection. It's wise to wear UVA and UVB-blocking sunglasses when the sun shines brightly.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Roppongi, Japan
- Average high temperature in September: 26.9°C
The warmest month (with the highest average high temperature) is August (30.6°C).
The month with the lowest average high temperature is January (8.8°C).
- Average low temperature in September: 21.5°C
The month with the highest average low temperature is August (24.9°C).
The coldest month (with the lowest average low temperature) is January (3°C).
Average pressure in September
Roppongi, Japan
- Average pressure in September: 1013.4mbar
The month with the highest atmospheric pressure is November (1018.1mbar).
The month with the lowest atmospheric pressure is June (1009.2mbar).
Average wind speed in September
Roppongi, Japan
- Average wind speed in September: 13km/h
The windiest month (with the highest average wind speed) is April (15.6km/h).
The calmest month (with the lowest average wind speed) is November (12.3km/h).
Average humidity in September
Roppongi, Japan
- Average humidity in September: 74%
The month with the highest relative humidity is July (79%).
The month with the lowest relative humidity is January (60%).
Average rainfall in September
Roppongi, Japan
- Average rainfall in September: 54mm
The wettest month (with the highest rainfall) is September (54mm).
The driest month (with the least rainfall) is February (10mm).
Average rainfall days in September
Roppongi, Japan
- Average rainfall days in September: 12.9 days
The month with the highest number of rainy days is July (16.1 days).
The month with the least rainy days is January (4.5 days).
Average snowfall in September
Roppongi, Japan
- Average snowfall in September: 0mm
The month with the highest snowfall is February (4mm).
The months with the least snowfall are March, April, May, June, July, August, September, October, November and December (0mm).
Average snowfall days in September
Roppongi, Japan
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (1.2 days).
The months with the least snowfall days are April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Roppongi, Japan
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 30min).
The month with the shortest days is December (Average daylight: 9h and 48min).
- Average sunshine in September: 7h and 48min
The month with the most sunshine is August (Average sunshine: 10h and 18min).
The month with the least sunshine is February (Average sunshine: 5h and 42min).
Average sunshine days in September
Roppongi, Japan
- Average sunshine days in September: 13.8 days
The month with the most sunshine days is January (25.4 days).
The month with the least sunshine days is June (11.5 days).
Average UV index in September
Roppongi, Japan
- Average UV index in September: 6
The month with the highest UV index is July (UV index 7).
The month with the lowest UV index is January (UV index 2).
Average cloud cover in September
Roppongi, Japan
- Average cloud cover in September: 41
The months with the most cloud cover are June and October (Cloud cover 44).
The month with the least cloud cover is January (Cloud cover 28).
Average visibility in September
Roppongi, Japan
- Average visibility in September: 10km
The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (10km).
The month with the lowest visibility is July (9km).
