Shanghai will get some relief from the recent heat wave when the high temperature falls to 34 C this weekend, the city's weather bureau predicted Wednesday.

With the exception of this weekend's forecast, Shanghai's weather will remain as it has been throughout most of this summer. Hot.

The high temperature has exceeded 35 C on 20 days this year, including 18 in the first 24 days of July, according to the Shanghai Meteorological Bureau.

The bureau issued an orange high temperature alert at 8:15 am Wednesday, the seventh orange alert so far this year. Weather officials issue the alert whenever the temperature is expected to surpass 37 C over the next 24 hours.

The temperature peaked Wednesday at 38.6 C, the highest so far this year, according to the bureau. Moreover, Tuesday was the hottest July 23 on record over the last 140 years.

The hottest summer on record was in 1934, when the high temperature surpassed 35 C on 55 days, including 23 in July alone. It was also the hottest July on record.

The weather bureau predicted Shanghai will experience another 10 days in which the high exceeds 35 C, said Wu Rui, the bureau's chief service officer.

The extreme heat has tested the city's power grid. Shanghai's peak electricity usage hit 28.02 million kilowatts Wednesday, breaking the previous record of 27.51 million kilowatts on July 11, according to Shanghai Municipal Electric Power Co.

To save electricity, the Shanghai Municipal Afforestation and City Appearance and Environmental Sanitation Administration turned off most of the city's landscaping lighting Tuesday and Wednesday evening, according to a report in the Oriental Morning Post.

The bureau promised to turn off all of the city's landscaping lighting when the temperature exceeds 38 C, though it made an exception for the lights on the Bund.

It has also decided to wait to turn on the lighting until 7:30 pm, a half hour later than usual. 

The weather bureau predicted the high temperature will be 38 C Thursday and 36 C Friday.