Temperatures of up to 42 degrees Celsius are forecast in areas of southwest China in the next few days, forcing schools to delay classes.

Temperatures will be as high as 40 to 42 degrees Celsius on Thursday in the eastern part of the Sichuan Basin and most of neighboring Chongqing, the two regions most severely affected by drought, said the China Central Meteorological Observatory.

Observatory stations in Chongqing, which reported temperatures of up to 40.8 degrees Celsius on Wednesday, have put residents on red alert for high temperatures.

The heat wave has forced schools, which normally open on September 1, to postpone classes, according to local education authorities.

In Suining and Guang'an of Sichuan, kindergarten, primary and middle school classes will begin on September 4 or 5. School is also delayed for a week in Anyue County of Sichuan.

But if high temperatures continue in these areas, school will be put off again, according to local education authorities.

The Chongqing Educational Commission issued an emergency notice Monday delaying student registration for all kindergartens, primary and middle schools.

Students will not register until September 5, said the notice. School opening times may be further adjusted if the new heat wave continues, it added.

Meanwhile, temperatures of 38 to 39 degrees Celsius are also forecast in central and eastern provinces such as Hunan, Hubei, Zhejiang and Fujian.

By last Saturday, some 17.5 million people and 16.6 million livestock were short of drinking water in China as a result of drought, according to the State Flood Control and Drought Relief Headquarters.