A depression in the Arabian Sea has intensified into a cyclonic storm, with heavy rains and gusting winds forecast for Mumbai and other parts of India's west coast, weather officials said on Wednesday.

Cyclone Phyan lay about 600 km south-southwest off Mumbai, and was moving in a north-northeasterly direction, said Ajit Tyagi, Director General of the Indian Meteorological Department.

"The system is likely to intensify further and cross south Gujarat and north-Maharashtra coast late in the night," he said.

Heavy to very heavy rains are expected during the day, with wind speeds of about 80 km an hour, he said.

Fishermen have been advised not to venture into the sea, and people living in low-lying areas have been asked to move.

At Mumbai's airport, the country's busiest, rain and windy conditions were causing delays of up to 40 minutes, a spokesman said.

The rains could hamper crushing of sugarcane in Maharashtra state, the country's top producer of sugar.

The final one-day international cricket match between Australia and India, scheduled to begin later on Wednesday in Mumbai, was also likely to be cancelled, TV news channels said.