BEIJING: The temperature in Beijing soared above 40 degrees Celsius on Thursday for the first time since 2014 and broke the record for the hottest day in June, with heatwaves that had seared northern China a week earlier expected to persist through the weekend.

A weather station in the southern suburbs of Beijing recorded 40.7C (105.3 Fahrenheit) at 2:30 p.m. (0630 GMT), according to the municipal weather bureau, marking the first breach of the 40C threshold since May 29, 2014.

Thursday was also Beijing's hottest day in the month of June since modern meteorological records began. The previous all-time high was logged on June 10, 1961, when the mercury rose to 40.6C.

Early on Thursday the city of nearly 22 million people raised an orange alert, the second-highest weather warning, saying that temperatures could rise as high as 39C in most parts of the city from Thursday to Saturday.

Beijing, Tianjin, Hebei and Shandong in northern and eastern China were hammered by heatwaves last week, prompting local authorities to step up efforts to safeguard crops, ensure the safety of tourists, and suspend outdoor work during the hottest part of the day.

Last week, the national weather bureau issued an alert for heat stroke, almost a fortnight earlier than in previous years, as new record temperatures for the month of June assailed cities across northern China.

In the port city of Tianjin, increased demand for air-conditioning pushed its power grid load to 14.54 million kilowatts on June 15, up 23% from a year earlier, and spurred its local utility department to dispatch workers to patrol underground tunnels every day to ensure electrical cables are in working order.

The latest round of heatwaves, coinciding with the Dragon Boat Festival long weekend in China, will also hit the northern Chinese region of Inner Mongolia and Xinjiang in the far west, according to the China Meteorological Administration.

China has a four-tier, colour-coded weather warning system, with red the most severe, followed by orange, yellow and blue.

An orange alert is issued when the maximum temperature exceeds 40C in a single day, or the maximum temperature remains above 37C for two consecutive days.