A worker pours a bottle of water on his face to cool off at a construction site in Yantai, Shandong province, June 16, 2023. (PHOTO / VCG)

SHIJIAZHUANG, Hebei – Many places in northern China including Beijing have been swept by heatwaves since Thursday with temperatures in some areas exceeding 40 C, triggering observatory authorities' alerts for high temperatures and advise for avoiding outdoor activities.

The National Meteorological Center renewed a yellow alert on Friday morning for high temperatures. It has a three-tier, color-coded warning system for such high temperatures, with red being the most severe warning, followed by orange and yellow.

The places with heatwaves in the recent three days were mainly caused by a warm ridge of high pressure in the atmosphere.

Zhang Fanghua, Chief forecaster, National Meteorological Center

Temperatures in some regions reached 37 to 40 C on Friday, including most places in the Beijing-Tianjin-Hebei region and mid-north parts of Shandong province, and some may even exceed 40 C.

"The places with heatwaves in the recent three days were mainly caused by a warm ridge of high pressure in the atmosphere," said Zhang Fanghua, a chief forecaster with the center, adding that relatively low humidity during the day is also conducive to rising temperatures.

According to the center's realtime temperature map at 2 pm on Friday, Beijing, Tianjin, most parts of Hebei and some neighboring areas were hit by the highest temperatures nationwide, which were all above 37 C. Beijing Meteorological Service issued an orange alert on Friday morning for the expected high temperatures from Friday to Saturday.

The observatory watchdog in Tianjin upgraded its orange alert to red on Friday morning while neighboring Hebei province renewed its red alert.

Meteorological authorities in the places hit by heatwaves advised locals to avoid outdoor activities during high-temperature periods in the afternoon and suggested that working units provide necessary protective measures for employees to avoid heatstroke.

"We have suspended the work for two days at most of our construction sites, while one or two are still under work for emergency," said Wang Xu, a project manager at a construction company in Shijiazhuang, Hebei. 

Employees still at work have been provided with protection, he added.