September weather forecastSendai, Japan

September

Weather in September

September in Sendai offers an invite to the autumn season with nature's vibrant displays coloring the cityscape. As September progresses, temperatures become more weather-friendly, encouraging more outdoor adventures. However, the temperate climate does not signify the cessation of rainfall. Clear skies become a frequent phenomena, commanding the attention of stargazers and photographers alike. The average temperature ranges between 17.5°C (63.5°F) to 23.9°C (75°F), pointing towards the gradual cooling that lies ahead.

Temperature

The commencement of September indicates a gentle shift in the average high-temperature, receding from August's 27.8°C (82°F) to a still moderately hot 23.9°C (75°F). During September, Sendai records a consistent average nighttime temperature of 17.5°C (63.5°F).

Humidity

The average relative humidity in September in Sendai is 80%.

Rainfall

In Sendai, in September, it is raining for 12.9 days, with typically 66mm (2.6") of accumulated precipitation. Throughout the year, in Sendai, there are 152.2 rainfall days, and 720mm (28.35") of precipitation is accumulated.

Snowfall

May through November are months without snowfall.

Sea temperature

In September, the average sea temperature in Sendai is 22.7°C (72.9°F).
Note: When thinking about a swim in 22.7°C (72.9°F) waters, consider your cold tolerance, the day's sunshine, wind, and air temperature. It is a fun fact that Olympic swimmers dive into waters of 25°C (77°F) to 28°C (82.4°F).

Daylight

The average length of the day in September is 12h and 27min.
On the first day of September in Sendai, sunrise is at 05:06 and sunset at 18:06. On the last day of the month, sunrise is at 05:31 and sunset at 17:21 JST.

Sunshine

In Sendai, the average sunshine in September is 7.7h.

UV index

In September, the average daily maximum UV index in Sendai is 5. A UV Index of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for ordinary individuals.
Note: The maximum daily UV index of 5 in September converts into the following recommendations:
Take precautions - Protection against sunburn is recommended. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes. Caution! The Sun's UV rays become stronger due to reflections from water and sand.

Updated: Jan 31, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

In September, the average high-temperature and low-temperature in Sendai, Japan, are 23.9°C (75°F) and 17.5°C (63.5°F) respectively. In August, the average heat index (a.k.a. 'feels like', 'real feel'), which combines relative humidity and air temperature, is appraised at 32°C (89.6°F).

In September, the average relative humidity in Sendai, Japan, is 80%.

In September, in Sendai, Japan, the rain falls for 12.9 days. Throughout September, 66mm (2.6") of precipitation is accumulated.

May through November are months without snowfall.

In Sendai, Japan, the average seawater temperature in September is 22.7°C (72.9°F). A person's cold intolerance, with sunshine, wind, and air temperature, are essential factors for enjoying swimming in 22.7°C (72.9°F) water.

The average day length in September is 12h and 27min.

On the first day of September in Sendai, Japan, sunrise is at 05:06 and sunset at 18:06. On the last day of the month, sunrise is at 05:31 and sunset at 17:21 JST.

In September, the average sunshine duration in Sendai, Japan, is 7.7h.

In Sendai, Japan, the average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a moderate vulnerability from exposure to Sun's UV rays.

Today

Tomorrow

Long-term

Year J F M A M J J A September O N D

Aug

September

Oct

Average high temperature

27.8°C

23.9°C

18.5°C

Average low temperature

Average pressure

Average wind speed

Average max. wind speed

9.7km/h

10.2km/h

12.9km/h

Average wind speed gusts

Average humidity

Average rainfall

Average rainfall days

Average snowfall

Average snowfall days

Average sea temperature

Average daylight

Average sunshine

Average sunshine days

10.6

14.1

16.3

Average UV index

Average cloud cover

Average visibility

Average temperature in September
Sendai, Japan

Average high temperature in September: 23.9°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 (3.3°C).

Average low temperature in September: 17.5°C

The month with the highest average low temperature is August (21.4°C).
The coldest months (with the lowest average low temperature) are January and February (-1.7°C).

Average pressure in September
Sendai, Japan

Average pressure in September: 1014mbar

The month with the highest atmospheric pressure is November (1018.7mbar).
The month with the lowest atmospheric pressure is June (1009.3mbar).

Average wind speed in September
Sendai, Japan

Average wind speed in September: 9.7km/h

The windiest month (with the highest average wind speed) is January (14.4km/h).
The calmest month (with the lowest average wind speed) is July (8.1km/h).

Average humidity in September
Sendai, Japan

Average humidity in September: 80%

The month with the highest relative humidity is July (84%).
The months with the lowest relative humidity are April and May (72%).

Average rainfall in September
Sendai, Japan

Average rainfall in September: 66mm

The wettest months (with the highest rainfall) are July and October (111mm).
The driest month (with the least rainfall) is February (22mm).

Average rainfall days in September
Sendai, Japan

Average rainfall days in September: 12.9 days

The month with the highest number of rainy days is July (20.7 days).
The month with the least rainy days is January (8.7 days).

Average snowfall in September
Sendai, Japan

Average snowfall in September: 0mm

The month with the highest snowfall is February (63mm).
The months with the least snowfall are May, June, July, August, September, October and November (0mm).

Average snowfall days in September
Sendai, Japan

Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (9.2 days).
The months with the least snowfall days are May, June, July, August, September, October and November (0 days).

Average sea temperature in September
Sendai, Japan

Average sea temperature in September: 22.7°C

The best month for swimming (with the highest average sea temperature) is August (23.9°C).
The coldest month (with the lowest average sea temperature) is March (7.5°C).

Average daylight in September /
Average sunshine in September
Sendai, Japan

Average daylight in September: 12h and 24min

The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).

Average sunshine in September: 7h and 42min

The month with the most sunshine is May (Average sunshine: 9h and 30min).
The month with the least sunshine is January (Average sunshine: 5h and 6min).

Average sunshine days in September
Sendai, Japan

Average sunshine days in September: 14.1 days

The month with the most sunshine days is November (17.6 days).
The month with the least sunshine days is July (7.2 days).

Average UV index in September
Sendai, Japan

Average UV index in September: 5

The months with the highest UV index are July and August (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).