The intense downpours and strong winds that hit northern China starting on Sunday will continue for an extended period in a wide range of areas, greatly increasing the risk of natural disasters, the National Meteorological Center said on Monday.
The rainfall in the region on Sunday and Monday was the heaviest since the flood season began in June and marks the start of northern China's monthlong rainy season.
Though heavy rain is common around this time of year, which marks the start of northern China's rainy season, "it has come a little earlier than in normal years," said Zhang Fanghua, the center's chief forecaster. The average duration of northern China's rainy season is from July 18 to Aug 18, she added.
The heavy rainfall in Beijing and Tianjin and in Hebei, Shanxi and Shandong provinces is similar to the extreme rains between July 18 and 20, 2016, that caused urban flooding, mountain torrents, mudslides, landslides and other disasters, she added.
The center forecast that starting on Tuesday, the heavy rain will move eastward as well as northward, so rainfall in Beijing and Hebei province will be significantly weakened.
The rainfall in the region on Sunday and Monday was the heaviest since the flood season began in June and marks the start of northern China's monthlong rainy season
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Between July 14 and 20, lighter rainfall is expected to linger in northern China and the Yangtze and Huaihe river regions, while Southwest China's Sichuan province will experience heavier rain than other places, the center said.
By Monday morning, heavy rain had closed several sections of highway in Hebei and Shanxi provinces, and many flights were canceled in Beijing, local authorities said. Hail also hit parts of Hebei province and Beijing.
Meteorological stations in Hebei's Jize county and Henan province's Huaxian county set records with precipitation of more than 200 millimeters, the center said.
Zhang, the meteorological center's forecaster, said the low vortex system, a type of cold low pressure, brought abundant water vapor and unstable energy to the northern areas.
"The system that usually moves slowly is a favorable condition for rain to last long and accumulate in certain areas," she said.
The National Meteorological Center had issued a yellow alert for heavy rain and another alert for thunderstorms on Monday. A yellow alert is the third-highest of a four-tier system, with red being the most severe, followed by orange, yellow and blue.
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The center said that when a yellow alert is issued, traffic management departments should take control measures based on road conditions and give traffic guidance. Other relevant departments should promptly clear drainage outlets.
It suggested that people avoid riding bikes or driving in the rain, and should shut off outdoor power sources in low-lying areas, refrain from outdoor activities in open areas and take care around dilapidated or damaged houses.
Meanwhile, for the next week in southern China, the Yangtze and Huaihe river regions are bracing for the summer's hottest, most sultry days, with little rain－a period that began on Sunday and could last for 40 days and bring temperatures above 35 C, the center said.