IMD Issues Orange Alert for Mumbai as Early Monsoon Triggers Heavy Rain, Disrupts City

Mumbai is expected to experience generally cloudy skies with the possibility of thunderstorms, lightning and gusty winds reaching 40-50 kmph today, according to the India Meteorological Department. IMD also issued a yellow alert for the city, reported The Indian Express.

This comes a day after heavy showers battered the city on May 25, leading to traffic congestion across multiple parts of the city. Commuters reported waterlogging and long delays on key arterial routes, according to Business Today.

The southwest monsoon is expected to advance to Mumbai and some other parts over the next three days, the IMD added.

The IMD also issued a warning of thunderstorms, rain and gusty winds in Dadar, Mahim, Parel, Bandra, Kalachowki and several other parts of the city.

"Conditions are favourable for further advance into some more parts of central Arabian Sea, more parts of Maharashtra including Mumbai, Karnataka including Bengaluru, some parts of Andhra Pradesh, remaining parts of Tamil Nadu, more parts of west-central and North Bay of Bengal and some more parts of North Eastern states during next three days," the IMD said.

So far, the coastal Konkan stretch and Mumbai have been witnessing heavy pre-monsoon rains over the last two days in Maharashtra.

Usually, the southwest monsoon marks its onset over Kerala by June 1 and covers the entire country by July 8. It starts retreating from northwest India around September 17 and withdraws completely by October 15. It normally reaches Maharashtra around June 7 and Mumbai on June 11.

Early Onset of Southwest Monsoon

IMD declared the early onset of southwest monsoon in Maharashtra on May 25 as southwest monsoon advanced into some parts of the state, about ten days ahead of the actual date of onset of June 5. According to The Indian Express, this is the earliest date of monsoon onset in Maharashtra since 1990.

In 1990, southwest monsoon made onset over Maharashtra on May 20, IMD scientist Sushma Nair said.

What Caused Early Onset?

According to The Indian Express, a combination of large-scale atmosphere-oceanic and local factors developed and favoured the early monsoon onset this year.

However, the onset took place under the conditions including the Madden Julian Oscillation, Mascarene High, Convection, the Somali jet, Heat-low, monsoon trough and pressure gradient and monsoon onset vortex, which play a key role in influencing good monsoon rainfall.

(With inputs from PTI.)