BEIJING, June 16 -- China's National Meteorological Center on Sunday morning continued to issue a yellow alert for high temperatures as multiple regions are experiencing sweltering heat.

The intensity of high temperatures is expected to decrease in north China and regions between the Yellow River and the Huaihe River, while the extent of the heat will also diminish in these regions, the center said.

During the daytime on Sunday, some areas in Xinjiang, Inner Mongolia, Gansu, Hebei, Beijing, Shandong, Henan, Anhui, Hubei and Hainan will see temperatures reaching 35 to 36 degrees Celsius, according to the center.

The center forecasts maximum temperatures of 37 to 39 degrees Celsius in parts of Xinjiang, Inner Mongolia and Henan.

Outdoor activities should be avoided during periods of high temperatures, and precautionary measures should be taken to protect vulnerable groups such as children and the elderly, the center said.

China has a three-tier warning system for high temperatures, with red representing the most severe warning, followed by orange and yellow.