Japan is entering the season known as "tsuyu," or the rainy season, leading up to the hot summer months. In this edition, we will introduce you to the nature of rain in Japan and explain how to calculate the appropriate rainfall for using rain chains.

“Tsuyu” - Rainy Season


In Japan, we have a season from spring to summer known as "tsuyu," characterized by many cloudy and rainy days. The Japan Meteorological Agency announces the start and end of the rainy season for various regions. Typically, tsuyu begins in June and ends around July. The Agency defines tsuyu as a period "from late spring to summer when rainy and cloudy days become frequent." This season affects our daily lives, leading to more frequent use of umbrellas and drying laundry indoors. Although it is a challenging period due to the high humidity, the end of tsuyu heralds the arrival of the hot summer months.

Expressions for Rainfall Intensity


There are various expressions to describe the strength and patterns of rain, but here we will introduce the terms used by the Japan Meteorological Agency. Rainfall between 10mm and 20mm is called "moderately heavy rain," indicating a downpour. Rainfall between 30mm and 50mm is termed "intense rain," describing rain that falls as if buckets of water were being emptied.

Reference: JMA Strength and patterns of rain

Rainwater Chains and Rainfall


Rain chains have a specific capacity for draining rainwater, so you need to determine the amount of rainfall you want to manage. The expected rainfall will vary depending on your region. Generally, the number of rain chains needed is based on the roof area and the expected rainfall. At SEO RAIN CHAIN, we provide an automatic calculation form to help you determine this, so please use it for your convenience. 

 SEO RAIN CHAIN Drain Cap Calculation Form



SEO RAIN CHAIN, manufactured in Toyama Prefecture of JAPAN, where highest rainfall levels are recorded in the country.


Toyama Prefecture, where our headquarters is located, is one of the regions in Japan with the highest annual rainfall and most rainy days.Despite having fewer sunny days, we focus on making rainy days more appealing by producing rain chains in Toyama Prefecture.SEO RAIN CHAIN actually shines on rainy days, making you look forward to the rain. Even on sunny days, these beautiful rain chains add a touch of richness to daily life. Consider incorporating our original rainwater chains into your home.