Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
The arrival of September corresponds with a temperature reduction, down from August's warm 27.8°C (82°F) to an agreeable 22.6°C (72.7°F). An average nighttime temperature of 13.4°C (56.1°F) is noted in Iiyama during the month of September.Humidity
In September, the average relative humidity in Iiyama is 83%.Rainfall
In Iiyama, in September, during 17.7 rainfall days, 70mm (2.76") of precipitation is typically accumulated. Throughout the year, there are 201.2 rainfall days, and 928mm (36.54") of precipitation is accumulated.Snowfall
In Iiyama, snow does not fall in May through October.Daylight
The average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 05:17 and sunset at 18:15. On the last day of September, sunrise is at 05:41 and sunset at 17:31 JST.
Sunshine
In September, the average sunshine in Iiyama is 8.6h.UV index
The average daily maximum UV index in September in Iiyama, Japan, is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for ordinary individuals.Note: A daily high UV index of 4 in September leads to these guidelines:
Act with care - The need to guard against sun damage is communicated. Direct Sun exposure should be minimized especially during midday when radiation is most intense. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun.
Frequently asked questions
What is the average September temperature in Iiyama?
What is the average humidity in September in Iiyama?
How many days does it rain in September in Iiyama?
When it does not snow in Iiyama?
What is the average length of the day in September in Iiyama?
What time are sunrise and sunset in September in Iiyama?
How many hours of sunshine does Iiyama have in September?
How high is the UV index in September in Iiyama?
Average temperature in September
Iiyama, Japan
- Average high temperature in September: 22.6°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 (0.8°C).
- Average low temperature in September: 13.4°C
The month with the highest average low temperature is August (17.7°C).
The coldest month (with the lowest average low temperature) is January (-6.5°C).
Average pressure in September
Iiyama, 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
Iiyama, Japan
- Average wind speed in September: 6.6km/h
The windiest month (with the highest average wind speed) is January (8.9km/h).
The calmest month (with the lowest average wind speed) is August (5.6km/h).
Average humidity in September
Iiyama, Japan
- Average humidity in September: 83%
The month with the highest relative humidity is January (87%).
The month with the lowest relative humidity is May (72%).
Average rainfall in September
Iiyama, Japan
- Average rainfall in September: 70mm
The wettest month (with the highest rainfall) is July (160mm).
The driest month (with the least rainfall) is November (47mm).
Average rainfall days in September
Iiyama, Japan
- Average rainfall days in September: 17.7 days
The month with the highest number of rainy days is July (24.9 days).
The month with the least rainy days is February (9.9 days).
Average snowfall in September
Iiyama, Japan
- Average snowfall in September: 0mm
The month with the highest snowfall is January (398mm).
The months with the least snowfall are May, June, July, August, September and October (0mm).
Average snowfall days in September
Iiyama, Japan
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (20.6 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Iiyama, Japan
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 36min).
The month with the shortest days is December (Average daylight: 9h and 42min).
- Average sunshine in September: 8h and 4min
The month with the most sunshine is August (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 5h and 0min).
Average sunshine days in September
Iiyama, Japan
- Average sunshine days in September: 9.1 days
The month with the most sunshine days is May (12.2 days).
The month with the least sunshine days is July (4.3 days).
Average UV index in September
Iiyama, Japan
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in September
Iiyama, Japan
- Average cloud cover in September: 41
The month with the most cloud cover is January (Cloud cover 51).
The month with the least cloud cover is May (Cloud cover 33).
Average visibility in September
Iiyama, Japan
- Average visibility in September: 8km
The months with the highest visibility are April, May and November (9km).
The months with the lowest visibility are January, February, March, June, July, August, September, October and December (8km).
Iiyama, Japan
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