Sendai Weather in September

 Season: Autumn
 Key points:
1.    Sendai’s weather in September is gradually getting cool, with some hot daytime usually in the early and middle periods.
2.    Sendai is scarcely rinsed by heavy rainfall but moistened by light rain from time to time in September.

Sendai in the Afternoon

Getting from Hot to Cool

The hot climate lingers sometimes in the daytime of early and mid-September, normally with the highest temperature of about 26-30 degrees Celsius (79-86 degrees Fahrenheit). However, there are possible circumstances that the highest temperature exceeds 34℃ (93℉) when it’s sunny. Therefore, if you are planning your 2026 Sendai trip in September, you’d better prepare some summer clothes and keep hydrated, just in case. Delightfully, it’s getting comfortably cool, particularly in late month, with the maximum temperatures of basically no more than 28℃ (82℉); and the night is accordingly much cooler than that of the previous period, at 14-20℃ (57-68℉), so you may need to add a thin coat outside your shirt.

Pavilion in Zuihoden

Highest Precipitation of the Year but Not Too Frequent

Sendai receives a total rainfall of about 211mm on average in September, the highest of the year. Fortunately, rainfall isn’t too frequent, about 13 days monthly. There may be 2-3 days of heavy rain, with the most being light rain. Therefore, you’d better check the weather forecast beforehand and avoid traveling in heavily rainy days, and prepare rain gear for other times.

Because of the high precipitation, the average humidity is as high as 78%. In sunny days after rainfall, especially in the first half of the month, you probably feel sticky.

Daylight Duration & Sunshine Hours

Sunrise time (1st-30th): 05:07 – 05:32
Sunset time (1st-30th): 18:09 – 17:23
Average daylight duration (1st-30th): from about 13 hours to 12 hours
Average sunny days: 14 days
Average sunshine hours: 7 hours

The daylength is shortening over the month, yet most of the daylight hours are sunny, which is beneficial for your outdoor sightseeing and recreation. However, the UV index should not be ignored; it averages around 5, perhaps even higher on clear days, so sun protection measures should be properly implemented.

Sendai in Sunny September

Packing Guide for Sendai Trip in September

 Clothing
Summer clothes like T-shirts, thin loose pants or shorts, and dresses are still appropriate during the daytime throughout September. The early mornings and evenings, especially in late September, are quite cool, so it’s recommended to add a light jacket over your summer clothes and change the shorts to thin long pants.

 Shoes
You can choose to wear sandals or canvas shoes depending on your preference; the former is much cooler, while the latter is more comfortable for walking.

 Others
Sunhat and sunscreen are significant to bring considering the moderate UV rays. For extra sun protection, you can wear sunglasses and sun protective suit. Besides, it’s necessary to pack an umbrella in your bag in case it rains.

Seasonal Event You May Be Interested In

Every year on the second weekend of September, the Jazz Festival is held in Sendai Jozenji. During this festival, about 700 bands from Sendai and other parts of Japan and abroad gather here, filling the streets and alleys with a joyful atmosphere of music. In addition to jazz, there are many other types of music being played, including Rock, Ska, Latin, and Gospel music.

Note: 
1.    The performance schedule will be published on the relevant local media in advance. If you want to secure a good spot, remember to arrive early.
2.    Both indoor and outdoor performances are available. If you choose to enjoy performance outdoors, be sure to take precautions against sunburn.

Travel Suggestions & Information You Might Need

 The Jazz Festival attracts a large number of tourists over the two days, but only a few large stage areas, such as Sendai Kotodai Park, will be crowded where performances from well-known musicians will be going on; other performance areas will be less crowded. If you want a peaceful experience, consider attractions like the Zuihoden, Aoba Castle, or Osaki Hachiman Shrine, other than those around the business streets.

Tranquil Zuihoden in September

 As the summer travel peak in July and August comes to an end, the ticket prices for flights and trains and accommodation fee in September will be more favorable.

Sendai Weather by Month