The mercury rose to 31.5 degrees Celsius in Hong Kong on Sunday – the highest temperature recorded in March since records began in 1884. The Observatory warned on Sunday that “[u]nder the persistent influence of a southerly airstream and plenty of sunshine, the weather will still be hot” on Monday. “The maximum temperature will be around 31 degrees in the urban areas.” The week will start off hot and dry, with rain expected into the weekend, the Observatory says. Meanwhile, Taiwan also saw unprecedented heat on Sunday. According to the Central Weather Administration, highs of 36 degrees Celsiu…