Global warming behind monsoon’s extended stay?

Mumbai: The thunder, lightning and rainfall every single evening of late have nailed one fact—the monsoon is in no hurry to retreat from the city. While its average withdrawal date is September 28, the monsoon has been stretching its stay to October in the past few years. 
    In 2005, when the city received record rainfall, it retreated on October 7. A year later, it withdrew in the second week of October. This trend continued till 2010, when it made its exit in the third week of October. 
    While weather experts are uncertain about reason behind the October shift, they agree that the monsoon pattern is changing. "The shift may be because of global warming, one cannot say for sure," said a former official from the Indian Meteorological Department (IMD). "Research on the subject is currently on and until it is complete, we cannot really point out the precise reason." 
    As of now, thunderstorms are likely to continue for a few more days. 3-4 dry days mark retreat of monsoon, says IMD 
Mumbai: N Y Apte, deputy director general at Indian Meteorological Department (IMD), Mumbai, said, "The upper air cyclonic circulation, which has been aiding the thunderstorms, is now weakening. We expect the thundershowers to continue for the next three days at least. After that, the city will require another few days as the cooling period. If the area fulfils the required criteria thereafter, the monsoon will be declared withdrawn," he said. 
    The meteorological department said that there are some criteria to mark the monsoon's withdrawal. "For any area, the main criterion is it should remain dry for three to four days," said Apte. Between Sunday and Monday, though, Colaba got 15mm rainfall and Santa Cruz 33.4mm. 
    The IMD said the monsoon normally starts withdrawing from north Gujarat by September 15 and, by October 1, from Goa, parts of Madhya Pradesh and Uttar Pradesh. It is expected to withdraw from Mumbai within this time span as well. Evidently, this is not the case this year either. 
    On Monday, the southwest monsoon further withdrew from most parts of Uttar Pradesh, Madhya Pradesh, Gujarat and Bihar. As of now, the withdrawal line of southwest monsoon passes through Raxaul, Varanasi, Jabalpur, Hoshangabad, Vadodara and Porbandar. 
    "We were expecting the monsoon to withdraw by September 30, since there had been no rainfall for a considerable period of time. However, thunderstorms started on October 1, because of which withdrawal has been out of question," said Apte and added that the withdrawal date for the western region is decided by IMD Delhi and Pune. 
    The southwest monsoon is from the southern peninsula and hence retreats from the entire country only after October 1, when the circulation pattern indicates a changeover from the southwesterly wind regime. 
Power supply snaps in parts of Mumbai T he city witnessed sporadic incidents of power failure following heavy thundershowers on Monday evening. According to the BEST control room, approximately 42 complaints were registered within two hours of showers in South Mumbai. Complaints were registered in Sion, Dadar, Worli, Mahim and Dharavi. According to Reliance Infrastructure, more than seven buildings experienced power cuts for a few minutes in suburban Mumbai. Complaints were registered in Santa Cruz, Khar, Borivli and Dahisar, RInfra sources said. In the satellite town of Kalyan-Dombivli, where the state distribution company MSEDCL supplies power, 30 complaints were registered. TNN

Since '05, monsoon has lingered till Oct