There will be a respite from the scorching temperatures in Shanghai today when rain hits the city again.

Temperatures will drop to 30 degrees Celsius but rise back gradually from tomorrow, which will be cloudy, the Shanghai Meteorological Bureau said.

After two days of cloudy weather - tomorrow and Wednesday - thunderstorms are expected from Thursday. Highs will be around 32 degrees, lows around 25 degrees.

Yesterday, the Summer Solstice, temperatures rose above 35 degrees and a thunderstorm hit the city in the afternoon.

The weather bureau issued rainstorm, lightning and gale alerts.

Forecasters said the tropical storm Linfa ("lotus" in the Macau dialect) prevented a rainbelt from the north reaching the city, which caused the weekend heat. Saturday was the hottest day of the year so far with a high of 37.4 degrees.

"Originally we expected thunderstorms to hit in the morning, but Linfa changed the atmosphere circulation, delaying the storm," said Man Liping, a forecaster with the bureau. "But the storm will not affect the city directly."