September weather forecastJoetsu, Japan
September
Weather in September
The first month of the autumn, September, is still a warm month in Joetsu, Japan, with an average temperature varying between 16.6°C (61.9°F) and 23.3°C (73.9°F).Temperature
The shift from August to September includes a small decrease in the average high-temperature, from a warm 27.8°C (82°F) to a still moderately hot 23.3°C (73.9°F). Joetsu, in September, observes a steady average low-temperature of 16.6°C (61.9°F).Humidity
In September, the average relative humidity is 80%.Rainfall
In September, in Joetsu, the rain falls for 16.5 days. Throughout September, 83mm (3.27") of precipitation is accumulated. Throughout the year, there are 200.6 rainfall days, and 1190mm (46.85") of precipitation is accumulated.Snowfall
May through October are months without snowfall.Sea temperature
In Joetsu, the average seawater temperature in September is 25.6°C (78.1°F).Note: Water temperature between 25°C (77°F) and 29°C (84.2°F) provides warmth and pleasure, making water activities enjoyable for lengthened periods without feeling uncomfortable.
Daylight
In Joetsu, the average length of the day in September is 12h and 26min.On the first day of September, sunrise is at 05:17 and sunset at 18:16. On the last day of the month, sunrise is at 05:41 and sunset at 17:32 JST.
Sunshine
In Joetsu, the average sunshine in September is 8.3h.UV index
In Joetsu, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the average person.Note: A daily maximum UV index of 5 in September translates into the following instructions:
Exercise prevention - Precautions against solar damage are endorsed. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses. Heed this! UV intensity is much stronger when reflected off sand and water.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Joetsu, Japan
- Average high temperature in September: 23.3°C
The warmest month (with the highest average high temperature) is August (27.8°C).
The month with the lowest average high temperature is January (2.8°C).
- Average low temperature in September: 16.6°C
The month with the highest average low temperature is August (20.9°C).
The coldest month (with the lowest average low temperature) is February (-1.9°C).
Average pressure in September
Joetsu, Japan
- Average pressure in September: 1013.9mbar
The month with the highest atmospheric pressure is November (1019.2mbar).
The month with the lowest atmospheric pressure is June (1009.2mbar).
Average wind speed in September
Joetsu, Japan
- Average wind speed in September: 9km/h
The windiest months (with the highest average wind speed) are January and December (15.4km/h).
The calmest months (with the lowest average wind speed) are July and August (7.7km/h).
Average humidity in September
Joetsu, Japan
- Average humidity in September: 80%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is May (74%).
Average rainfall in September
Joetsu, Japan
- Average rainfall in September: 83mm
The wettest month (with the highest rainfall) is July (142mm).
The driest month (with the least rainfall) is May (57mm).
Average rainfall days in September
Joetsu, Japan
- Average rainfall days in September: 16.5 days
The month with the highest number of rainy days is July (21.6 days).
The month with the least rainy days is February (10.3 days).
Average snowfall in September
Joetsu, Japan
- Average snowfall in September: 0mm
The month with the highest snowfall is January (466mm).
The months with the least snowfall are May, June, July, August, September and October (0mm).
Average snowfall days in September
Joetsu, Japan
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (17.4 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average sea temperature in September
Joetsu, Japan
- Average sea temperature in September: 25.6°C
The best month for swimming (with the highest average sea temperature) is August (27°C).
The coldest month (with the lowest average sea temperature) is March (10.3°C).
Average daylight in September /
Average sunshine in September
Joetsu, Japan
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 42min).
- Average sunshine in September: 8h and 18min
The month with the most sunshine is August (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 2h and 42min).
Average sunshine days in September
Joetsu, Japan
- Average sunshine days in September: 11.5 days
The month with the most sunshine days is May (15.1 days).
The month with the least sunshine days is January (4.3 days).
Average UV index in September
Joetsu, Japan
- Average UV index in September: 5
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Joetsu, Japan
- Average cloud cover in September: 39
The month with the most cloud cover is January (Cloud cover 74).
The month with the least cloud cover is May (Cloud cover 35).
Average visibility in September
Joetsu, Japan
- Average visibility in September: 9km
The months with the highest visibility are October and November (10km).
The month with the lowest visibility is January (8km).
