THE World Expo site survived its toughest test to date after thunderstorms and torrential rain hit the city last night, disrupting flights and flooding streets.

But the drainagesystem at the Expo site withstood the onslaught, authorities said.

The site recorded its biggest rainfall this year with up to 91.5 millimeters noted at the Puming Pump Station. The average rainfall at the Expo site was above 80 millimeters. But officials said any flooding in the site was soon drained and that the drainagesystem had "passed the hardest test this year."

Yesterday's weather was fine, sunny to cloudy, during the day but the sky gradually darkened from about 4pm and thunder and lightning struck from mid evening.

The Hongqiao International Airport said at least 69 flights were disrupted by the storms - 60 were delayed, six canceled and three forced to land at the Pudong International Airport.

Shanghai Flood Control Headquarters said at least 20 streets were flooded in Baoshan District and the Pudong New Area. About 46 households in three residential areas in the Sanlin area of Pudong were flooded.

Shanghai Meteorological Bureau issued a yellow rainstorm alert, third highest of the four-level system, yesterday at 3pm. The alert was later upgraded to orange at 8:50pm at the Expo site. A yellow thunder alert, lightest of the three-level system, and a yellow gale alert, lightest of the three-level system, were also issued yesterday afternoon.

The rainstorm alert was lifted at 10:45pm.

Similar weather, sunny to cloudy in the morning with thundery showers in the afternoon or evening, should continue throughout the weekend and into next week, the bureau said.

Temperatures yesterday reached 35.8 degrees Celsius in the morning, making it the 29th high-temperature day this year, the bureau said.

Today is forecast to be showery with thunder and temperatures ranging from a low of 27 degrees to a high of 34 degrees.

Tomorrow should be cloudy with thundery showers with a low of 27 degrees and a high of 33 degrees, the bureau said.

• system [´sistəm] n.系统，体系，制度 (初中英语单词)
• rainfall [´reinfɔ:l] n.雨量 (初中英语单词)
• thunder [´θʌndə] n.雷 vi.打雷 vt.吼出 (初中英语单词)
• lightning [´laitniŋ] n.闪电 a.突然的 (初中英语单词)
• international [,intə´næʃənəl] a.国际的，世界的 (初中英语单词)
• headquarters [´hed,kwɔ:təz] n.总部(署)，司令部 (初中英语单词)
• bureau [´bjuərəu] n.局；编辑部；事务所 (初中英语单词)
• yesterday [´jestədi] n.&ad.昨天；前不久 (初中英语单词)
• drainage [´dreinidʒ] n.排水(设备)；排水法 (英语四级单词)
• weekend [´wi:kend, ,wi:k´end] n.周末休假 (英语四级单词)
• forecast [´fɔ:kɑ:st] vt.&n.预测；预报 (英语六级单词)