BEIJING -- Some localities in China have postponed the start of the autumn semester for high schools, primary schools and kindergartens due to relentless heat.

In Nanchang, capital city of East China's Jiangxi province, some counties and districts have delayed the autumn semester for primary schools in their jurisdictions due to hot weather, according to the Nanchang education bureau.

The new semester starting dates are at the discretion of local education authorities, the bureau said.

The Nanchang meteorological observatory on Sunday night issued an orange alert for high temperatures, the second-highest level in the country's color-coded alert system, forecasting that the majority of the city would be in the grip of high temperatures of above 37 degrees Celsius over the next 24 hours.

In Southwest China's Sichuan province, several cities have announced the postponement of the start of the fall semester. For example, education and sports authorities in the city of Nanchong decided that the start of the fall semester for high schools, vocational schools, primary schools and kindergartens should be postponed by a week.

The meteorological observatory of Chengdu, the capital city of Sichuan, on Monday morning upgraded its previous orange alert for high temperatures to a red alert, the highest of the color-coded system, marking the 9th high temperature red alert the city has issued this year.

The observatory forecast the temperature would reach 40 degrees Celsius and higher in some parts of the city within the next 24 hours.

"The start date of school has been postponed by one week to Sept 8. Currently, we are working overtime to install air conditioning in student dormitories," said Cheng Dong, a management staff member at Sichuan College of Architectural Technology, while adding that the school is also ramping up heatstroke prevention measures and emergency response preparations.

Education authorities in multiple districts and counties in Southwest China's Chongqing municipality announced last Wednesday that the start of the fall semester for high schools, primary schools and kindergartens would be delayed due to the scorching heat.

On Monday, the Chongqing meteorological observatory issued a high temperature red alert, forecasting that temperatures in many parts of the city would exceed 40 degrees Celsius.