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Heatstroke And Japanese Summer - More Than Just Heat

Heatstroke And Japanese Summer - More Than Just Heat

Translated by MATCHA

Written by MATCHA-PR

2015.05.29 Bookmark

In Japan you will often see signs reminding people to prevent heat stroke in the summer - so what are the best ways? Let's have a look!

For those who have yet to experience it, summers in Japan can be difficult to imagine.

Japanese summers last from roughly the end of May to about the end of September. While May tends to be pleasantly sunny and warm, the rest of the summer is different. As most of Japan lies in the tropical to northern temperate climate zone, the weather is much hotter and more humid than most visitors to the area would expect. Before making the journey to Japan, especially in the summer, it is vital that you prepare for weather that you might not have encountered before. Serious medical conditions may arise if you are ill-prepared, and no one wants to visit the hospital on vacation.

In this article, we will take a closer look at some of the weather related problems that may arise during the summer in Japan.

Japan's Summer Begins with the Rainy Season


When summer officially begins at the start of June, the rainy season called tsuyu begins and lasts for roughly a month in the central regions of Japan (excluding Hokkaido). Following this month of damp to humid rainy weather, Japan enters its hottest and most humid season, with daily temperatures ranging from 25°C to 35°C (77-95°F) or more, and with humidity reaching around 80% or sometimes even higher. In weather like this anyone can start to feel ill if they stay outside for too long.

Tsuyu is very important for farmers, and help rice crops to prosper. It wouldn't be an exaggeration to say that it's a supporting factor in Japan's culinary culture. The intensity of the rainy season varies year to year; some years you may barely see the sun in June while in others there may be small cloudbursts daily but overall sunny weather.


Temperatures can suddenly drop due to the heavy rainfall during this period, so it is a good idea to bring a light jacket or sweater with you when you are going to be out all day.

The Temperature Rises Suddenly When Tsuyu Ends


When tsuyu ends, July begins with a sudden sharp rise in both heat and humidity. This is known as tsuyu-ake, and is the perfect time to head to the beach, pool or water park, or to get of the city in favor of the cooler mountain areas. If you stay in the city, you will notice a distinct change in business attire; known as "Cool Biz", the majority of companies allow their employees to switch out suits for short sleeve shirts or summer dresses.

The most important thing to watch out for during the summer is heatstroke or sunstroke.

What is Heatstroke/Sunstroke?


A relatively common condition in Japan, many visitors to this area, especially those from more northern regions may not have heard of this serious and potentially fatal medical issue before.

Heatstroke or sunstroke, is a direct result of prolonged exposure to intense heat or overexertion in hot/humid temperatures. Essentially, this exposure causes the temperature-regulating mechanisms in your body to malfunction, which then causes your body to lose the ability to manage its other systems, leading to permanent muscle or organ damage, brain damage or even death if not treated quickly.

The symptoms of heatstroke include: high fever, an altered mental state (such as slurring, agitation, confusion), dizziness that gets worse over time, nausea/vomiting, feeling faint or lightheaded, throbbing headaches, and/or rapid, shallow breathing. Heatstroke does not hit all at once, but rather comes on slowly, but the faster that it is treated, the better. Annually in Japan up to 1000 people (mainly the elderly) die from heatstroke each year.

In Japanese, heatstroke is called necchūshō (熱中症), pronounced phonetically in English as: "neh-chew-show".

What to Watch Out for


Whenever doing heavy work or physical activities under strong/direct sunlight is the time when you should be most aware of heatstroke, though there are also cases where poorly air-conditioned or ventilated indoor facilities can cause heatstroke as well.

As a result, both crowded indoor and outdoor tourist attractions can be dangerous on the hottest days of the summer. For those who are not used to weather such as this, your own body may not be adequately prepared to adjust to these temperatures as quickly as needed, creating a higher risk of heatstroke for travelers from more moderate climates.

For travelers who aren't used to Japan's summers, heatstroke is something that must be watched out for and ideally, prevented.

What Can I do To Protect Myself?

1. Get Out of the Heat!


If you start finding yourself thinking "It's so hot, I'm starting to feel tired/ill..." then it's important to quickly find a place with plenty of shade where you can sit and cool down.

If you're inside your hotel or hostel room, adjust the temperature with a fan or air-conditioning, take off any excessive layers of clothing and try placing a cool wet towel or wrapped ice pack on your head.

Before you go out for the day, make sure you have a cap or sunhat to protect from the sun, and if you can, try to stay out of the direct sunlight (especially during the hottest part of the day). Make sure to wear loose clothes that breathe, in light colors.

2. Keep Hydrated!


Photo by hauptillusionator

When you lose water to perspiration, it's easy to become dehydrated; the symptoms of mild to moderate dehydration are similar to those of heatstroke, and also include dry mouth, thirst despite drinking and tiredness (especially in children). Severe dehydration is a medical emergency just like heatstroke, so please be aware of you and your travel companions' fluid intake.

That being said, if you drink too much at once, you could further imbalance your body's electrolyte levels and potentially make yourself feel worse. The best idea is to have water or a sports' drink on you at all times and to drink whenever you feel the slightest bit thirsty. It is hard to judge just how much fluid you should take in, but if you find that you are sweating a lot more than you would back home, you should be drinking more than you would normally.

Surviving Summer in Japan

Though we discussed some pretty serious issues in this article, with a proper understanding of the weather in Japan and careful self-management, heatstroke and dehydration can be entirely avoided. We know it is easy to forget to drink and things like that when you are having a great time, but wouldn't you rather look back on your trip with fond memories of the sights and not of hospitals?

Remember, if you or your travel companion(s) start to feel ill, prioritize your well-being and get help right away. Have a good, safe trip!

Movie: Be Careful of Heatstroke

Need More Summer Advice?

The information presented in this article is based on the time it was written. Note that there may be changes in the merchandise, services, and prices that have occurred after this article was published. Please contact the facility or facilities in this article directly before visiting.

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