The region may receive up to 250 mm rainfall during the period, said the India Meteorological Department (IMD).
"Areas such as Mumbai, south Gujarat, Konkan, Goa and west Vidarbha will get extremely heavy rainfall in the next 24 to 48 hours. It is a serious situation. We have issued necessary warnings to departments concerned, including airports," AK Srivastav, head of climate monitoring and analysis at IMD Pune, told news agency PTI.
"Till yesterday, we were expecting heavy rainfall but after going through satellite images and their pattern, we have issued a forecast for extremely heavy rainfall," he said.
"The status of the weather system, which has brought heavy showers over the Mumbai region, has been upgraded from 'well marked low pressure' to 'depression'. It means it is set to bring more rains. Hence, we have predicted an extremely heavy rainfall in the next 24 to 48 hours," he said.
Mr Srivastav said the weather system's intensity has increased in the last couple of days.
"The weather system developed in the southern part of India and moved towards the central parts above Chhattisgarh. Then it moved towards the west coast and brought more showers on Gujarat, the Mumbai region, Konkan and north Madhya Maharashtra."
"It is getting more moisture from the Arabian sea and hence its intensity has increased in the last couple of days," the IMD official said.