Temperatures to increase as 'Summer Begins'
The seventh solar term Lixia, or Summer Begins, started on Wednesday, the final day of the five-day May Day holiday.
It indicates rising temperatures and more rain in the Jiangnan areas (regions south of the Yangtze River).
The maximum temperature is expected to increase from 24 degrees Celsius on Thursday to 32 degrees on Sunday, while the lowest will rise from 16 to 20, the Shanghai Meteorological Bureau said.
Although light rain is forecast on the first working day after the holiday, the rest of the week should be dry.
Air quality will be good on Thursday but slightly polluted on Friday and Saturday due to high concentrations of PM10 particles and ozone (O3), the Shanghai Ecology and Environment Bureau said.