Climate & Weather in Okinawa

Post date: Wednesday, August 2, 2017

For foreign expats moving to Okinawa from overseas countries as well as ones moving to the island from other areas in Japan, we here provide the guidance on Okinawa weather. We will be happy if it could help you to prepare for your seasonal clothing and more for your life in Japan.

Okinawa region belongs to a subtropical climate having a warm climate throughout the year and the annual average temperature is around 23℃. It has many fine days from the end of the rainy season in June to around October, and has many cloudy and rainy days in the winter. In the spring the weather changes periodically and gradually gets muggy toward the rainy season. In the summer the number of the typhoon passage or approaches increases resulting in approximately 7 passages or approaches of typhoon recorded in an average year. Okinawa weather is fairly mild and generally quite pleasant though there is a typhoon (also known as a hurricane or tropical cyclone) season that runs from May to December when the weather can get very bad, very quickly if a storm is passing by.

Rainfall Level & Average Temperature in Okinawa (2019)

The below is the Rainfall Level and Average Temperature in Okinawa (Naha City). Rainfall is more frequent from March through October, during which includes Rainy Season in May-June and Typhoon peak season in August-September in the city. When you see a change of temperature for one year, it becomes the lowest in January and the highest in July. One of the distinctive characteristics of Okinawa climate is very little difference between the highest temperature and the lowest temperature in a day. The other characteristic is that it is not so cold in the winter and even the minimum temperature becomes no less than 10 ℃ in the coldest winter time in a year. The humidity is high throughout the year, and the monthly average relative humidity in the winter is a little less than 70% and it reaches more than 80% in the rainy season.

  Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sept. Oct. Nov. Dec.
Rainfall Level (mm) 55 156.5 183.5 128 208.5 595.5 284 208 477.5 104.5 136 100.5
Max.Temp ( °C) 20.7 22.7 22.4 24.9 27 29 31.5 31.8 30.7 28.6 25.6 22.6
Ave.Temp ( °C) 18.1 20 19.9 22.3 24.2 26.5 28.9 29.2 28 26 23.1 20
Min.Temp ( °C) 15.8 17.7 17.5 20.2 21.9 24.4 26.8 27.3 26.1 24.2 21 17.8

Average Temperature & Humidity in Okinawa (2019)

  Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sept. Oct. Nov. Dec.
Ave.Temp ( °C) 18.1 20 19.9 22.3 24.2 26.5 28.9 29.2 28 26 23.1 20
Ave.Temp ( °F) 64.58 68 67.82 72.14 75.56 79.7 84.02 84.56 82.4 78.8 73.58 68
Humidity (%) 67 79 70 78 74 89 84 83 82 75 70 73

The highest temperature in Okinawa summer is around 32 - 33℃ having very few extremely hot day more than 35℃, and it is lower than in most of the regions of Main land in Japan (except for Tohoku region). This is because Okinawa Island's land area is small and surrounded by the sea, and it has no big city such as Tokyo and Osaka and seldom causes heat island effect. But it is difficult to spend the summertime without an air-conditioner, and careful attention and preparation is necessary to prevent heat strokes as humidity becomes so high under the influence of wet sea breeze.

Seasonal Clothing (for Naha City & Vincinity)

  • Spring (Mar. - May) : Light clothing, short sleeves
  • Summer (Jun. - Aug.) : Short sleeves
  • Autumn (Sep. - Nov.) :same as Spring
  • Winter (Dec. - Feb.) : Jacket, sweater

The best times to visit are from February, for the well-known blooming of cherry blossoms, to April with pleasant weather before the rainy season, and also October-November for enjoyable climate. It has a lot of squall-like heavy rains during the rainy season in May and June, and it can get hot and extremely muggy bringing the typhoon season during July - September. The winter time is also recommended because it is relatively warm and very few tourists may relax you. It is also helpful for you to see Seasonal Clothing idea above.

The Weather in Okinawa and Advice for Every Season

Okinawa (Naha City) is an urbanized city and most people get around using public transit, bikes, or their feet. Here are a few tips & tricks to make surviving close encounters with Mother Nature a little easier:

■ Precipitation:

Because Okinawa has squall-like short time rain suddenly and frequently even in a fine day, and a weather forecast is difficult and not successful, there seems to be many people who do not carry an umbrella. Local people may think it is easy to take shelter without an umbrella because the rain passes shortly and strong sunlight may come back soon, and it may dry wet clothing immediately. If you don’t like to be wet in the rain, however, you can always duck into the nearest convenience store for a cheap umbrella—they're everywhere!

■ Heat:

It can get quite hot in Okinawa so dress accordingly. If you're going to work, check and see if your office follows a "cool biz" dress code which is a set of comparatively relaxed dress guidelines encouraged by the Japanese government to help make life more comfortable for office-workers in the summer. People wearing a local cool clothing which is a short-sleeved wing-collared shirt called "Kariyushi" can be seen in Okinawa work places in this season.