The monsoon officially arrived in Mumbai on Saturday and hit the city and other parts of Maharashtra with full fury, disrupting flights, the suburban train system and road traffic, besides claiming two lives, officials said.

The Indian Meteorological Department has forecast heavy rains with thundershowers in the city and suburbs over the next 48 hours, with isolated extreme heavy rainfall in some areas till Monday.

There were at least two incidents of building crashes here as water-logging was reported from several parts and in adjoining Thane, one person was electrocuted and another was killed due to a lightning strike.

At least two firemen were injured when a portion of a dilapidated building on fire suddenly crashed in south Mumbai's Fort area earlier.

Four persons sustained minor injuries when the roof of a four storeyed building Munji House crashed at Prabhadevi in central Mumbai late on Friday.

Flights at the Mumbai airport were affected, with Jet Airways announcing delays of around 40 minutes for departures and 20 minutes for arrivals due to congestion and bad weather till 3 p.m.

The BrihanMumbai Municipal Corporation said south Mumbai experienced 33.10 mm rains while the suburbs notched 33.80 mm rains till noon, as it continues to rain in most parts.

Owing to waterlogging in parts of central Mumbai like Dadar east, Parel, Sion, Kings Circle and surroundings, traffic was hit badly and diversions were implemented to prevent snarls.

While the suburban train services on the Central Railway were delayed by around 15 minutes, the services on Western Railway remained largely unaffected by the rains.

The coastal districts of Sindhudurg, Ratnagiri, Raigad, Thane and Palghar also received heavy rains as the monsoon spread across the state bringing relief from the sultry heat experienced in the past few weeks.