田吹 遥子 
According to the Japan Meteorological Agency (JMA), Okinawa’s rainfall total for the month of May came in at around 4,578 millimeters, the highest level since rainfall levels began being recorded in 1967. The totals, which were recorded at the Okinawa Meteorological Observatory’s seven weather observation locations, this year’s totals were three times the average annual totals. Before this year, the highest recorded total was 2,332 millimeters, recorded in May of 2020. That record was 1.5 times the previous record.
The JMA manages 25 locations in Okinawa where they observe weather, and amongst those Naha, Nago, Kume Island, Miyakojima, Ishigaki Island, Iriomote Island, Yonaguni Island, and Minamidaito are called the above-ground weather observation stations. These eight locations have recorded measurements dating back to 1967. The record is determined by comparing seven of these locations, excluding Minamidaito which has a different climate.
From the seven observation locations, the total May rainfall totals for the location which exceeded three times the annual average were as follows – Miyajojima: 815 mm. (avg. 222.3 mm), Iriomote Island: 582 mm. (avg. 176 mm.), Yonaguni: 666 mm. (avg. 207 mm.), and Ishigaki Island: 588 mm. (avg. 191 mm.).
According to the JMA, the factors that caused the high rainfall include La Niña and erratic prevailing westerlies, as well as a tendency for the rainy season’s storm front to get held up over the Okinawa region. Additionally, there is the powerful South Pacific High in the ocean south of Japan, and the wet air that flows south in force from the edge adds to the already wet conditions of the rainy season.
If the rainy season storm front is active up until March, there is a chance that it will bring a lot of rain with it. According to the weather forecast announced by the JMA in March, the rainfall was predicted to be slightly below average.
(English translation by T&CT and Sam Grieb)
Go to Japanese https://ryukyushimpo.jp/news/entry-1526965.html
