SHANGHAI - Shanghai issued a red alert for high temperatures on Wednesday, the fifth one issued thus far this year, as the Chinese lunar calendar says "autumn begins".

Temperatures are expected to exceed 40 degrees Celsius in the city on Wednesday.

Sweating through the hottest July on record, Shanghai saw a record-high temperature of 40.6 degrees Celsius on July 26.

The previous record was set in 1934, when a temperature of 40.2 degrees Celsius was recorded.

A new record for consecutive hot days was also recorded in July, with temperatures exceeding 38 degrees Celsius for eight straight days.

The heat is expected to linger in Shanghai until Sunday, when a subtropical high that has boosted temperatures in the city will move north, the municipal meteorological station said.

China uses a three-tier color-coded warning system for high temperatures, with red representing the hottest weather, followed by orange and yellow.