FUZHOU - China's meteorological authorities issued a warning on Sunday about excessively high temperatures that are expected to hit southern China for the next few days.

The mercury is set to hover between 35 and 37 C in parts of Sichuan province and Chongqing municipality in Southwest China as well as in most areas south of the lower reaches of the Yangtze River and in the eastern portions of South China, the National Meteorological Center said in a statement on its website.

And temperatures could edge up to between 38 and 39 C in some of those places, it added.

In East China's Fujian province, the local meteorological authority issued an orange alert on Sunday because of the high temperatures, the second most serious level in China's four-color heat warning system.

High temperatures that had already tortured the provincial capital of Fuzhou for two days by Sunday following torrential rains at the end of last month were expected to remain around 38 C for the following three days, meteorologists said.

And Fuzhou is likely to see the hottest days the year during the second half of July, when thermometers might soar up to 40 C in some places, meteorologists predicted.

To prevent pedestrians from fainting in the scorching heat while waiting to cross roads, the city has set up 1,350 sunshades at main traffic intersections.

Air conditioners have been selling well in the city since the start of the heat wave. A sales manager surnamed Chen at Gome Electrical Appliances' Baolong outlet in Fuzhou said the store has been selling about 40 air conditioners a day recently.

"Customers usually won't buy air conditioners until the hottest days come," he said. "But many of them cannot wait now because the temperature is already too much to bear."

At night, city parks are crowded with people exercising in the relative cool.

"I have been staying in rooms with air conditioning during the daytime, so I want to go out and get some fresh air in the park when the temperature cools down at night," said Lin De, a 37-year-old Fuzhou resident.

In Shanghai, the mercury topped 38 C on Sunday.

"It felt hard to breathe with the temperature so high," said Huang Wenfang, a tourist from the cooler Northeast China. "I planned to stay a few days more in Shanghai but now I have changed my mind."

The city's swimming pools, seaside areas and air-conditioned public facilities saw large crowds on Sunday. Due to safety concerns, some water parks had to turn people away.

"We had to ask some swimmers to come back an hour later," said a ticket seller at a swimming pool attached to the Shanghai International Gymnastics Center.

Meteorologists predicted that the weather in Shanghai will cool down a little starting on Tuesday, when the city expects some rain and a high of 35 C.

In Chongqing, the temperature climbed to 38.9 C on Saturday, the highest recorded temperature for that date for six decades. On Saturday, up to 30 people fainted or felt uncomfortable and were taken to hospitals because of the heat, local media reported.

Hot weather will persist in Chongqing for three more days and the temperature there could slip past 40 C, according to the local weather forecast.

Unlike hot and dry southern China, rain is forecasted for the nation's north.

Parts of the Xinjiang Uygur autonomous region, Qinghai province and Northeast China will see moderate rain, while storms are expected along the Yellow River and the Huaihe River.

Wang Zhenghua in Shanghai contributed to this story.