Beijing's weather department issued a weather alert on Sunday afternoon as torrential rain fell in the capital and a cleaning worker was killed by lightning at Beijing Capital International Airport.

Thundershowers are also forecast for Monday morning, the Beijing Meteorological Bureau said.

The bureau issued a yellow weather alert at 3 pm, saying flooding was likely in rivers and mountain streams.

The meteorological authority uses a four-tier color-coded weather warning system, with red being the most severe, followed by orange, yellow and blue.

From 7 am to 5 pm on Sunday, the average precipitation of the city's main urban area was 23.2 mm and the heaviest was 100.8 mm in the Qinglongqiao area of Haidian district, according to the bureau.

Zhang Pu, head of the team that oversees the flooding emergency team for the Beijing Drainage Group Co, said that an emergency plan had been started in the city on Sunday for possible flooding under bridges as more rains were forecast that night.

Worker dies

Witnesses at Beijing Capital International Airport said that a worker was found unconscious on the parking apron of Terminal 3 after loud thunder and lightning at 8 am, the Beijing News reported.

Airport authorities confirmed he had been struck by lightning.

He was taken to a nearby hospital where he was pronounced dead, the report said.

By 5 pm on Sunday, Beijing Capital International Airport had canceled 279 flights and postponed 196 others. Air China canceled 102 flights and rescheduled 39 by the early afternoon.

China Southern delayed 128 of 221 flights and canceled 12. All 59 of the company's flights after 7 pm were canceled, according to the company's micro blog.

Bryson Miller, from the US, was stranded at the airport after he arrived in Beijing at around 2 pm for a transfer to Harbin, capital of Heilongjiang province.

"It was a 10 pm flight. Now it's scheduled to be 1 am. So three hours delayed," he said.

"Here on the departure level, where there are a lot of departures, it's just crowded. It's comparable to a train station during the new year," he said.