'Heat island effect' and approaching typhoon push street temperatures towards 42 Kowloon City was the hottest place in the city yesterday, with temperatures reaching 36.9 degrees Celsius, according to the Observatory. But a Post survey found temperatures experienced by people on the street were much higher, hitting 41.9 degrees on Hoi Pa Street in Tsuen Wan. Other places in the city, including Sham Shui Po's Pei Ho Street Municipal Services Building, Mong Kok's Ladies Market and Kowloon City, saw temperatures between 35 and 36.6 degrees in the afternoon. Leung Wing-mo, senior scientific officer, said the discrepancy between the readings of the Post and the Observatory was due to different measurement methods. The Observatory places a thermometer inside a box about 1.5 metres above ground to measure the temperature, while the Post took the readings on the street, directly under the sun. 'It is not representative if the temperature is measured at random locations. But those street readings might offer some idea of how people feel,' he said. The Observatory said the hot weather was the result of the influence of Typhoon Fung-wong. 'As the typhoon is moving inland, we expect the weather to become a bit cooler today, with occasional showers,' said Tsui Kit-chi, senior scientific officer. The temperature is expected to hover between 28 and 31 degrees today. Mr Tsui said yesterday's temperatures did not break any records, though they were the highest so far this year. The top temperature recorded at the Observatory's headquarters in Tsim Sha Tsui yesterday was 34.6 degrees. The highest recorded July temperature at the Observatory's headquarters was 35.7 degrees, in 1968. For air quality, Tap Mun was the worst, recording 202 on the air pollution index, followed by Sha Tin, Central and Western district, and Sham Shui Po. The hot weather also caused a few cases of heatstroke. A 59-year-old Nestle worker, taking part in a sit-in protest outside the company's Yuen Long headquarters, and a 56-year-old man elsewhere were admitted to hospital. The Senior Citizens Safety Association said that as of 5pm, it had received 997 alarm calls from the elderly, including 67 who were admitted to hospital for breathing problems or dizziness. The high temperatures increased concerns about the 'heat island effect' - when concrete and asphalt absorb the heat from the sun and release it at night. 'The city centre keeps getting hotter and the winters are coming later,' said Man Chi-sum, chief executive of Green Power. 'The government should have a policy to improve the heat island effect.' Dr Man said the government should consider installing underground water pipes to absorb the temperature, add greenery in the city centre and create more open space. A Kowloon City grocer surnamed Wong said some newly built high-rise buildings had driven temperatures there up. 'I am suffering the wall effect caused by the buildings. I find it difficult to breathe sometimes,' she said.