September weather forecastObu, Japan

September

Weather in September

September, the first month of the autumn in Obu, is still a warm month, with temperature in the range of an average low of 20.7°C (69.3°F) and an average high of 28°C (82.4°F).

Temperature

The transition into September involves a small decrease in the average high-temperature, dipping slightly from a hot 32.5°C (90.5°F) in August to a moderately hot 28°C (82.4°F). Obu encounters a steady low-temperature average of 20.7°C (69.3°F) throughout the month of September.

Heat index

In September, the average heat index is computed to be a tropical 31°C (87.8°F). If one persists in activity during exposure, it could induce weariness and subsequently, heat cramps.
When assessing, remember that heat index measurements are for light winds and shaded spots. Direct sunlight can potentially boost the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'feels like', blends air temperature and moisture content to represent the felt temperature to humans. An individual's temperature experience can be influenced by extra factors, including metabolic differences, activity levels, and clothing. When exposed to direct sunlight, it's possible for the heat index to increase by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are of high significance for children. Young people are generally more susceptible than adults because they perspire less. Furthermore, their proportionally larger skin surface to their petite bodies and the increased heat output from their actions add to the risk.

Humidity

In September, the average relative humidity in Obu is 74%.

Rainfall

In Obu, Japan, during September, the rain falls for 13.5 days and regularly aggregates up to 94mm (3.7") of precipitation. In Obu, during the entire year, the rain falls for 142.7 days and collects up to 863mm (33.98") of precipitation.

Snowfall

March through November are months without snowfall.

Daylight

The average length of the day in September is 12h and 25min.
On the first day of the month, sunrise is at 05:24 and sunset at 18:19. On the last day of September, in Obu, sunrise is at 05:46 and sunset at 17:37 JST.

Sunshine

The average sunshine in September in Obu, Japan, is 8.5h.

UV index

In Obu, Japan, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV radiation for the ordinary person.
Note: A daily high UV index of 5 in September leads to these guidelines:
Undertake protective steps - Obligation to safeguard skin and eyes from harm is in place. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage.

Frequently asked questions

The high-temperature, in September, in Obu, is 28°C (82.4°F), while the low-temperature averages to 20.7°C (69.3°F). The average heat index (a.k.a. 'apparent temperature', 'felt air temperature'), which takes the relative humidity and factors it into the air temperature reading, in September is computed to be 31°C (87.8°F).

In Obu, Japan, the average relative humidity in September is 74%.

In Obu, Japan, in September, during 13.5 rainfall days, 94mm (3.7") of precipitation is typically accumulated.

In Obu, snow does not fall in March through November.

The average day length in September in Obu is 12h and 25min.

On the first day of September, sunrise is at 05:24 and sunset at 18:19. On the last day of the month, sunrise is at 05:46 and sunset at 17:37 JST.

In September, the average sunshine duration is 8.5h.

In September, the average daily maximum UV index in Obu is 5. A UV Index of 3 to 5 symbolizes a medium hazard to health from unsafe exposure to Sun's UV rays.
Average high temperature
Average low temperature
Average wind speed
Average max. wind speed
Average wind speed gusts
Average humidity
Average rainfall
Average rainfall days
Average snowfall
Average snowfall days
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Obu, Japan

  • Average high temperature in September: 28°C

The warmest month (with the highest average high temperature) is August (32.5°C).
The month with the lowest average high temperature is January (8.1°C).

  • Average low temperature in September: 20.7°C

The month with the highest average low temperature is August (24.7°C).
The coldest month (with the lowest average low temperature) is January (1.6°C).

Average pressure in September
Obu, Japan

  • Average pressure in September: 1013.1mbar

The month with the highest atmospheric pressure is November (1019.1mbar).
The month with the lowest atmospheric pressure is June (1009.1mbar).

Average wind speed in September
Obu, Japan

  • Average wind speed in September: 9.1km/h

The windiest months (with the highest average wind speed) are January and February (11.8km/h).
The calmest months (with the lowest average wind speed) are June and July (8.6km/h).

Average humidity in September
Obu, Japan

  • Average humidity in September: 74%

The month with the highest relative humidity is July (78%).
The month with the lowest relative humidity is February (68%).

Average rainfall in September
Obu, Japan

  • Average rainfall in September: 94mm

The wettest month (with the highest rainfall) is July (165mm).
The driest month (with the least rainfall) is January (25mm).

Average rainfall days in September
Obu, Japan

  • Average rainfall days in September: 13.5 days

The month with the highest number of rainy days is July (19.2 days).
The month with the least rainy days is January (8.1 days).

Average snowfall in September
Obu, Japan

  • Average snowfall in September: 0mm

The month with the highest snowfall is January (18mm).
The months with the least snowfall are March, April, May, June, July, August, September, October and November (0mm).

Average snowfall days in September
Obu, Japan

  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (2.6 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
Obu, 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 54min).

  • Average sunshine in September: 8h and 30min

The month with the most sunshine is August (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 5h and 36min).

Average sunshine days in September
Obu, Japan

  • Average sunshine days in September: 13.9 days

The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is July (9.8 days).

Average UV index in September
Obu, Japan

  • Average UV index in September: 5

The months with the highest UV index are July and August (UV index 7).
The months with the lowest UV index are January and December (UV index 2).

Average cloud cover in September
Obu, Japan

  • Average cloud cover in September: 40

The month with the most cloud cover is July (Cloud cover 46).
The month with the least cloud cover is November (Cloud cover 33).

Average visibility in September
Obu, Japan

  • Average visibility in September: 9km

The month with the highest visibility is February (10km).
The month with the lowest visibility is July (8km).