The great diversity
Located in the northern hemisphere, Japan experiences the same seasons as Europe. However, Japan's surface area and its dual exposure to the Pacific and the Sea of Japan have created varied and sometimes paradoxical climates. Two currents, one cold (oyashio) and the other warm (kuroshio), meet in the Sea of Japan and the Pacific. The cold current descends from Siberia, while the warm current rises from the equator.
In Tokyo, the cold winter winds come from the north-west and load up with water as they pass over the Sea of Japan, ending up as snow on the western slope. This phenomenon explains the impressive snowfalls in the interior of Tōhoku, particularly in Yamagata, Aomori and Akita, where several meters of snow are often measured.
In summer, tropical winds blow up both sides of the mountains, bringing heavy rainfall in June and September, while July and August can become very hot and humid.
In some Tōhoku towns, such as Morioka or Fukushima, winter temperatures regularly drop below -5°C, while summers remain moderately warm. While winter is dry and cold in Tokyo, on the other side, on the Sea of Japan, the weather remains overcast and the sky dotted with long snow squalls. The west coast of Tōhoku, exposed to these winds, is directly affected.
Rainy and typhoon seasons
This is the term used in Japan for the rainy season. Known here as tsuyu, it generally lasts six weeks, from June to mid-July, although in recent years it has become shorter and shorter. The rain is heavy, the humidity soars and the atmosphere is muggy, but the showers are also interspersed with moments of calm. The Japanese summer also sees the arrival of typhoons, frequent between August and October, with a peak in early September. Rainfall is abundant and winds violent. This phenomenon is not taken lightly, and every year, especially in rural areas, there is considerable loss of life and material damage. In addition to the typhoon itself, floods, landslides and mudslides can be deadly. The Meteorological Agency announces the typhoon itinerary a few days in advance. Tōhoku is less exposed than the south of the country, but the Pacific coasts, such as Miyagi or Fukushima, may be affected. Other disasters can strike Japan at any time. These include volcanic eruptions (which can nevertheless be predicted); the Zao region, between Yamagata and Miyagi, is being closely monitored. Another risk is earthquakes, which are frequent and harder to predict. They can cause terrible tsunamis when they occur offshore. On March 11, 2011, a powerful earthquake off Japan's west coast triggered a violent tsunami, which struck several prefectures and killed tens of thousands. Tōhoku (and in particular the prefectures of Miyagi, Iwate and Fukushima) was the epicenter of this historic disaster. This large-scale natural disaster revealed the archipelago's shortcomings, particularly in the nuclear field, as the two Fukushima power plants were severely damaged by the earthquake. In Japan, there is a before and an after to March 11, 2011. But more than a decade later, Tōhoku continues to rebuild, between memory, reinforced prevention and resilience.
