September weather forecastIwanai, Japan
September
Weather in September
The first month of the autumn, September, is also an enjoyable month in Iwanai, Japan, with an average temperature ranging between max 19.6°C (67.3°F) and min 12.3°C (54.1°F).Temperature
In Iwanai, the average high-temperature in September gently drops from a warm 23.3°C (73.9°F) in August to a comfortable 19.6°C (67.3°F). Throughout September, the average low-temperature dips to a cool 12.3°C (54.1°F).Humidity
The average relative humidity in September is 84%.Rainfall
In Iwanai, in September, during 17.9 rainfall days, 74mm (2.91") of precipitation is typically accumulated. In Iwanai, Japan, during the entire year, the rain falls for 157.1 days and collects up to 887mm (34.92") of precipitation.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September is 12h and 31min.On the first day of September, sunrise is at 05:02 and sunset at 18:13. On the last day of the month, sunrise is at 05:34 and sunset at 17:21 JST.
Sunshine
In Iwanai, Japan, the average sunshine in September is 7.6h.UV index
In Iwanai, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV rays for the average person.Note: A typical high UV index of 4 in September suggests the following recommendations:
Take necessary precautions - Suggestions to elude sunburn are provided. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Iwanai, Japan
- Average high temperature in September: 19.6°C
The warmest month (with the highest average high temperature) is August (23.3°C).
The month with the lowest average high temperature is January (-3.8°C).
- Average low temperature in September: 12.3°C
The month with the highest average low temperature is August (16.1°C).
The coldest month (with the lowest average low temperature) is February (-8.9°C).
Average pressure in September
Iwanai, Japan
- Average pressure in September: 1013.4mbar
The month with the highest atmospheric pressure is November (1016.4mbar).
The month with the lowest atmospheric pressure is July (1008.4mbar).
Average wind speed in September
Iwanai, Japan
- Average wind speed in September: 9.6km/h
The windiest month (with the highest average wind speed) is December (14.5km/h).
The calmest month (with the lowest average wind speed) is August (8km/h).
Average humidity in September
Iwanai, Japan
- Average humidity in September: 84%
The months with the highest relative humidity are January and February (89%).
The month with the lowest relative humidity is April (79%).
Average rainfall in September
Iwanai, Japan
- Average rainfall in September: 74mm
The wettest month (with the highest rainfall) is August (105mm).
The driest month (with the least rainfall) is April (52mm).
Average rainfall days in September
Iwanai, Japan
- Average rainfall days in September: 17.9 days
The month with the highest number of rainy days is August (19.1 days).
The month with the least rainy days is January (3.4 days).
Average snowfall in September
Iwanai, Japan
- Average snowfall in September: 0mm
The month with the highest snowfall is December (598mm).
The months with the least snowfall are June, July, August and September (0mm).
Average snowfall days in September
Iwanai, Japan
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (28.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Iwanai, Japan
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 7h and 36min
The months with the most sunshine are May and August (Average sunshine: 8h and 24min).
The month with the least sunshine is January (Average sunshine: 1h and 24min).
Average sunshine days in September
Iwanai, Japan
- Average sunshine days in September: 8.6 days
The month with the most sunshine days is May (13.3 days).
The month with the least sunshine days is January (2.7 days).
Average UV index in September
Iwanai, Japan
- Average UV index in September: 4
The months with the highest UV index are July and August (UV index 5).
The months with the lowest UV index are January, February, March, November and December (UV index 1).
Average cloud cover in September
Iwanai, Japan
- Average cloud cover in September: 43
The month with the most cloud cover is January (Cloud cover 86).
The month with the least cloud cover is September (Cloud cover 43).
Average visibility in September
Iwanai, Japan
- Average visibility in September: 8km
The months with the highest visibility are April, May and October (9km).
The months with the lowest visibility are January, February, July, August and December (7km).
