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Record heat, excessive rain in some areas made for an 'abnormal' July: JMA

The surface temperature for central Japan is displayed in this image taken by the Earth observatory satellite Shikisai on Aug, 1, showing places with higher temperatures in dark red and cloud cover in white. (Image courtesy of JAXA)

TOKYO -- Record high temperatures and excessive rain in some areas combined for "abnormal weather" conditions in July, according to data released by the Japan Meteorological Agency (JMA) on Aug. 1.

The average temperature in July in eastern Japan including the Kanto-Koshin, Tokai and Hokuriku regions was 2.8 degrees Celsius higher than an average year, marking a record since weather statistics were first kept in 1946. The average temperature in western Japan including the Kinki, Chugoku, Shikoku and Kyushu regions showed a 1.6 degree increase from an average year, tying the second-highest figure on record. Meanwhile, the amount of rainfall on the Pacific Ocean side of western Japan was twice the level of an average year due to torrential rains and typhoons.

Weather forecaster Motoaki Takekawa summarized July as having, "Abnormal weather as the probability of torrential rains and intense heat over the same period is less than once every 30 years."

According to the JMA, two high-pressure systems extending from the Pacific Ocean and Tibetan Plateau caused the scorching heat. A record-high temperature of 41.1 degrees was observed in the Saitama prefectural city of Kumagaya on July 23. Across the country, 108 of 927 observation sites recorded their highest monthly temperatures. More than 100 observation spots experienced consecutive daily maximum temperatures of at least 35 degrees from July 14 to July 26, as the intense heat continued.

The duration of sunshine in July on the Sea of Japan side of eastern Japan was 179 percent compared with an average year -- the most ever recorded. Sunshine periods in western Japan were 130 percent of an average year.

Meanwhile, the amount of rainfall in July was especially high in western Japan due to torrential rains and Typhoon Jongdari, which moved west along the Japanese archipelago in an extremely rare behavior for a typhoon in this season. Rainfall for all of July was 225 percent compared to an average year in the Kinki region, 216 percent in the Sanyo area including Okayama and Hiroshima prefectures and 210 percent in the Shikoku region. Some 124 observation sites in places including Hiroshima Prefecture and the Gifu prefectural city of Takayama saw record rainfall over 48 hours between July 5 and July 8 due to the torrential rains.

The scorching heat is expected to continue until midway through August due to a high pressure system from the Tibetan Plateau spreading over Japan, according to the JMA. However, the weather may change abruptly in some areas because a weakening of the high-pressure system in the Pacific Ocean will allow warm and humid air to blow toward the Japanese archipelago from the south.

(Japanese original by Kazuki Mogami, City News Department)

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