SHANGHAI will ride a temperature roller coaster this week, forecasters said.

A broad trough of low pressure triggered by Typhoon Mangkhut and a weak cold front from the north met and brought heavy rains to the city on Sunday night.

Most areas of the city recorded more than 20 millimeters of accumulated rain during the night, according to the meteorological bureau.

Chongming Island was the wettest district. Between 4pm on Sunday and yesterday noon, precipitation reached 345.7 millimeters in the ecological park in Miaozhen Town with readings of 253.9 millimeters in Xincun Middle School.

The downpour helped to cool the city. Yesterday, Xujiahui weather observation station recorded a maximum 26.5 degrees Celsius.

Today will be overcast to cloudy, with scattered showers, and the high will return to 30 degrees, forecasters said.

A tropical high will move west and take control of the city tomorrow. As a result, the mercury will continue to climb. The high tomorrow is set to reach 31 degrees and it will further rise to hit 33 degrees on Thursday. There may be thunderstorms in the afternoon or at night.

A new cold front will arrive on Friday, bringing rain and lowering temperatures.

The high will fall to as low as 26 degrees.