Rain to return at the weekend
The plum rain belt is expected to return to Shanghai over the weekend with showers or thundershowers, forecasters said.
The weather on Friday morning will be similar to Thursday, mostly overcast and cloudy. The plum rain belt is likely to affect the city during the late afternoon with increasing clouds. Rain will fall at night and the wet conditions will continue into Saturday.
Heavy to torrential rain may arrive between Friday night and Saturday with rain cloud clusters moving east to the city.
The rain belt will move southward on Sunday and Monday with dry and cloudy weather returning. But from Tuesday, it will come north to dump a new round of rain on Shanghai. After that, the subtropical high pressure will get stronger and move northward, bringing afternoon showers and higher temperatures.
The high will remain at 28 degrees Celsius on Friday but drop to 25 degrees due to the rain. Then it will bounce back from 29 to 31 between Sunday and Thursday. It is likely to climb to 33 and 34 on Friday and Saturday next week. The lows will be between 22 and 24 degrees.
Shanghai will enter the hottest period of summer, sanfu, on Friday, which will last until August 21, according to the local weather bureau.
Figures from the benchmark Xujiahui weather station between 1981 and 2010 show that the number of high-temperature days — days with a high above 35 degrees — was 15 on average from June to August. And 10 of those days were between mid-July and mid-August, the sanfu period.
But there were still some summers with fewer or no high-temperature days during sanfu. For instance, the middle and late period of the 40-day sanfu in 2009 didn't have a high-temperature day, while 1999's sanfu had no high-temperature days.