The beginning of Japanese summer is marked by tsuyu, the rainy season. The weather during the rainy season is unstable and rain can occur at any time. This season is usually characterized by light and misty rains with high humidity and high temperatures.
Japan’s rainy season occurs during the transition from spring into summer. Atmospheric pressure over the Pacific Ocean rises, pushing the continental air north over Japan where the seasonal rain front becomes stagnant. The results are many days of rainy and cloudy weather. It affects all parts of Japan except for the northernmost island of Hokkaido.
So now, you’re probably wondering just how bad this rainy season. Don’t be afraid; visiting Japan during the rainy season has its positive aspects!
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Rainy Season in Tokyo
Rainy season in Japan starts around the end of May in Okinawa and goes until the end of July in the Japan mainland. The amount of rainfall differs depending on the region as well as on each area’s proximity to the ocean.
The beginning of the rainy season is called tsuyu-iri and the end of the rainy season is tsuyu-ake. The exact dates or the period during which the rainy season occurs differ each year. In Tokyo, the rainy season usually starts around the middle of June and lasts for about a month.
During the rainy season, it does not rain everyday. For example, the probability of rain in Tokyo is 45% during the peak of the rainy season and the probability of sunny weather is 27%.
Rainy Season Survival Kit
If you’re traveling to Japan during the rainy season, don’t forget to pack a raincoat, rain boots, and a small towel. Of course, the most important item in a “survival kit” for Japan’s rainy season is an umbrella. In Japan, you can find a whole array of umbrellas, coats, and boots, from elegant to simple adorable designs. Shopping for something special when it rains is sure to brighten your mood. If you can’t find a design you like, the famous transparent umbrellas are always an easy choice!
The main impact of the rainy season is the humidity that the season brings. The humidity of the rainy season creates conditions perfect for mold to grow, making it important to avoid mold growth by airing out your suitcases or closets when the sun finally does come out.
“Refresh sheets” are sold in Japan during the hot and humid seasons. They are used to wipe away the sweat from your body and can help make you feel better. While refresh sheets are used more often in the later summer months, you might still use them during tsuyu when it can get just as humid and disgusting outside.
Lastly, to fight the gloom of the rainy season, Japanese people love to hang “Teruteru Bozu” on the eaves on roofs. Teruteru bozu, literally “sunshine monks”, are small traditional handmade dolls made of white paper or cloth. Hanging them on the eaves, according to local lore, wards off rain and attracts good weather. Children often make them when they want the following day after a rainy one to be sunny.
Positive Things About the Rainy Season
Although the weather might not be the best for a holiday, there are some positive aspects of traveling in Japan during the rainy season.
Ajisai (Hydrangea)
The blooming of hydrangeas accompanies the rainy season in Japan. While they are pretty even without the rain, they are especially beautiful while full of raindrops. Large, flourishing hydrangeas are a sign of tsuyu and also a sign that you should take lots of pictures of them before they shrivel up in the dry heat. Expect to find vibrant shades of blues, purples, and pinks. In the Tokyo area, definitely consider a day trip to Kamakura as there are many temples, such as Hase-dera, that are famous for its hydrangeas.