Met unsure when rains will hit Goa

Panaji: With the onset of the southwest monsoon over Kerala likely to be delayed by three days, uncertainty prevails over its progress in Goa as convectional systems forming in the Bay of Bengal or Arabian Sea can effectively disrupt the monsoon current.
While conditions are favourable for its advancement into some parts of south Bay of Bengal and Nicobar islands over the next two days, it may hit Kerala three days late, by June 4.For Goa, higher on the western board, the normal date for onset of the monsoon is June 7, but IMD, Panaji, declined to comment on the matter.
“More details on this aspect will be released in about 10 days,” an official said.
In the past, the system has hit Goa even four days instead of a week, but it gets stuck at Karwar quite often due to various factors.
Forecasting monsoon advancement over Goa is a tricky issue, M R Ramesh Kumar, a reputed meteorologist and former chief scientist at the National Institute of Oceanography, Dona Paula, said.
“Any convectional activity either in the Bay of Bengal or Arabian Sea within the next fortnight can further complicate its advancement not only in the southern state but also over the entire Indian subcontinent,” he said.
The northern limits of monsoon advancement indicate how the complex system travels. “The progress of the monsoon is not in a linear fashion but highly irregular. In one year (2013), it covered the entire Indian subcontinent in just 16 days,” the meteorologist said. But in another year (2002), it took as long as 76 days.
Similarly, the history of its advancement shows its fickleness and variability. “June 1 being the mean monsoon onset date over Kerala, the earliest onset record is on May 11, 1918 – 20 days in advance,” Kumar said.
In comparison, the most delayed one was on June 18, 1972; 17 days behind schedule.
As per another parameter used by IMD, the onset of monsoon seven days early or seven days late (a standard deviation) is considered normal.