Take an umbrella to work as the annual plum rain season begins today, according to city weather experts.

Rain, thunderstorms, high humidity, or all three, are expected from today until next Tuesday. However, the weather will remain warm.

The maximum temperature will range between 28 to 32 degrees Celsius from today to Sunday, with lows of between 22 to 24 degrees, the Shanghai Meteorological Bureau said yesterday.

The good news is that from next week the weather will become cooler for a brief spell.

The highs of next Monday and Tuesday will be about 26 to 27 degrees, after lows of 21 to 23, according to the bureau, but rain will continue.

During the plum rain season, maximum temperatures may reach above 35 degrees, and once it ends the city faces some real scorchers.

"The plum rain season will last at least until July," said Li Jinyu, a forecaster with the bureau. "A total of 260 millimeters is expected to fall during the season, a bit more than the same period for the past few years."