Mumbai: The monsoon has officially arrived in Mumbai on Monday, marking it the earliest monsoon onset in the recent history. "Southwest monsoon 2025 has onset over Mumbai on 26th May 2025," Indian Meteorological Department (IMD) Mumbai informed. The official date of monsoon arrival in Mumbai is June 11.
As per IMD data, in the years 1956, 1962 and 1971, the monsoon arrived in Mumbai on May 29. This will also be the earliest onset of monsoon for the island city in the last 15 years.

With the early arrival of monsoon, an Orange alert for rainfall and thunderstorms has been issued for Mumbai, Thane and Palghar for May 26.
The city is lashed with heavy rainfall with thunderstorms since Sunday night. Mumbai has already recorded above average May rainfall this year, marking the wettest May month. As of May 25, Colaba observatory recorded 159.2 mm and Santacruz observatory recorded 164.3 mm of rainfall.
The heavy downpour has resulted in water logging in low-lying areas, disrupted suburban railway service and road traffic disruptions.
The Monday morning rainfall has affected the office goers in the peak hours. In just one hour - 9 am to 10 am, Nariman Point witnessed the heaviest downpour, with 104 mm rainfall recorded. The areas which followed are: Colaba with 83 mm, CSMT with 80 mm, Malabar Hill with 63 mm.