Rumoi Subprefecture is located in the northwest region of Hokkaido in Japan.To the north are the Sarobetsu wilderness and Soya, to the south are the Mashike mountainous district and Ishikari, to the east are the Teshio mountainous district as well as Kamikawa and Sorachi, and to the west is the Sea of Japan which Rumoi Subprefecture faces as it stretches 130km north to south and 60km east to west .
The area's topography features hillsides that extend close to the coast as well as flat terrain along the rivers. To the north, the expansive Sarobetsu wilderness, designated as a national park, encompasses the area from the Teshio River watershed to Soya.
The coast, which stretches 178km north to south, is known fondly as the Sea of Japan Ororon Line. It is a region surrounded by natural wonder and beauty including picturesque landscapes both along the Teshio River and inside Shokanbetsu-Teuri Yagishiri Quasi National Park.
Rumoi Subprefecture enjoys a Sea of Japan climate which makes it relatively warm compared to its northern latitude. Due to the elongated north-south shape of the Subprefecture, however, there is also an average annual temperature difference between the north and south of two degrees Celsius.
Heavy winter snows begin to melt around the beginning of April. Temperatures around this time rapidly warm up, with light winds and calm seas prevailing from June to August. The average summertime temperature is around 25 degrees Celsius, which offers a refreshing break from other parts of Japan where high temperatures and humidity are the norm. Even during the summer though, temperatures cool off sharply during the evening and early morning, so visitors are recommended to bring along a light jacket just in case.
Autumn passes rather quickly, with the first snowfall usually occurring at the end of October. The volume of precipitation increases steadily from autumn into winter, with interior sections of Rumoi Subprefecture recording as much as 2 meters of snow in one season. Harsh northwesterly winds strengthen during the winter months. These winds often blow in excess of 72km/h(45mi/h) and whip up the Sea of Japan into waves taller than 5 meters. The winter temperature can also dip to as low as minus 10 degrees Celsius, so visitors are recommended to dress appropriately on days when the winds are strong.
