This year's monsoon has reached 80 per cent of India so far, India Meteorological Department's senior scientist Dr Naresh Kumar told NDTV on advancement of southwest monsoon in the country. Monsoon reached different parts of the country rapidly due to a low pressure area occurring in the Bay of Bengal yesterday, he said. Monsoon arrived in Delhi and Mumbai on the same day on Sunday. This has happened after 62 years, Dr Kumar said.