September weather forecastKoshihara, Japan
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Koshihara, Japan, with an average temperature ranging between max 28.5°C (83.3°F) and min 27.3°C (81.1°F).Temperature
Koshihara, Japan, marks the onset of September with an average high-temperature of a still warm 28.5°C (83.3°F), a subtle shift from August's 29.4°C (84.9°F). Koshihara's average low temperature, barely cooler than the daytime high, steadies at a still moderately hot 27.3°C (81.1°F) during September.Heat index
For September, the heat index is evaluated at a hot 33°C (91.4°F). Take more safety measures, heat exhaustion and heat cramps are potential outcomes. Persistent activity might lead to heatstroke.The metrics for the heat index are tailored for both shady environments and light winds. The heat index can potentially augment by 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'feels like', is a single figure representing how weather conditions feel when combining temperature and humidity. One's weather perception can be influenced by a range of factors including metabolic differences, being pregnant, and their level of physical activity. Direct sunlight can potentially raise the heat index by 15 Fahrenheit (8 Celsius) degrees, so it's crucial to consider. Heat index values are especially vital to children. Youngsters typically face more danger than adults since they sweat less. Their larger skin surface compared to their small bodies and heightened heat production from their activities augment their vulnerability.
Humidity
The average relative humidity in September is 79%.Rainfall
In September, in Koshihara, Japan, the rain falls for 20.1 days. Throughout September, 139mm (5.47") of precipitation is accumulated. In Koshihara, Japan, during the entire year, the rain falls for 227.4 days and collects up to 1405mm (55.31") of precipitation.Daylight
In Koshihara, the average length of the day in September is 12h and 19min.On the first day of the month, sunrise is at 06:09 and sunset at 18:48. On the last day of September, sunrise is at 06:21 and sunset at 18:16 JST.
Sunshine
In Koshihara, Japan, the average sunshine in September is 8.4h.UV index
June through September, with an average maximum UV index of 7, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV rays for average individuals.Note: In September, an average UV index of 7 transforms into the following instructions:
Take precautions and utilize sun safety practices. Protection against skin and eye damage is required. The Sun's UV radiation is most potent between the hours of 10 a.m. and 4 p.m. Try to avoid direct sunlight during this time. Always opt for UVA and UVB-resistant sunglasses on radiant days.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Koshihara, Japan
- Average high temperature in September: 28.5°C
The warmest month (with the highest average high temperature) is August (29.4°C).
The month with the lowest average high temperature is January (18.9°C).
- Average low temperature in September: 27.3°C
The month with the highest average low temperature is August (28.3°C).
The coldest month (with the lowest average low temperature) is January (17°C).
Average pressure in September
Koshihara, Japan
- Average pressure in September: 1009mbar
The month with the highest atmospheric pressure is January (1020.8mbar).
The month with the lowest atmospheric pressure is August (1006.6mbar).
Average wind speed in September
Koshihara, Japan
- Average wind speed in September: 22.9km/h
The windiest month (with the highest average wind speed) is December (28.4km/h).
The calmest month (with the lowest average wind speed) is May (20.1km/h).
Average humidity in September
Koshihara, Japan
- Average humidity in September: 79%
The month with the highest relative humidity is June (86%).
The month with the lowest relative humidity is January (72%).
Average rainfall in September
Koshihara, Japan
- Average rainfall in September: 139mm
The wettest month (with the highest rainfall) is June (201mm).
The driest month (with the least rainfall) is February (59mm).
Average rainfall days in September
Koshihara, Japan
- Average rainfall days in September: 20.1 days
The month with the highest number of rainy days is June (21.5 days).
The month with the least rainy days is July (16.4 days).
Average daylight in September /
Average sunshine in September
Koshihara, Japan
- Average daylight in September: 12h and 18min
The month with the longest days is June (Average daylight: 13h and 42min).
The month with the shortest days is December (Average daylight: 10h and 30min).
- Average sunshine in September: 8h and 24min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 18min).
Average sunshine days in September
Koshihara, Japan
- Average sunshine days in September: 7.3 days
The month with the most sunshine days is July (11.9 days).
The month with the least sunshine days is December (5.7 days).
Average UV index in September
Koshihara, Japan
- Average UV index in September: 7
The months with the highest UV index are June, July, August and September (UV index 7).
The month with the lowest UV index is December (UV index 4).
Average cloud cover in September
Koshihara, Japan
- Average cloud cover in September: 38
The month with the most cloud cover is January (Cloud cover 63).
The month with the least cloud cover is July (Cloud cover 34).
Average visibility in September
Koshihara, Japan
- Average visibility in September: 10km
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
