Hyderabad: The life-giving monsoon season in India this year is under a cloud, of sorts. With the Indian Meteorological Department (IMD) saying that it expects what it calls a ‘normal monsoon’ this year, and private weather forecaster Skymet begging to differ - though just a bit slightly – enough uncertainty has been created just how this year’s monsoon will turn out into.
The IMD made it clear on Monday, that it expects a normal monsoon this year. Skymet in its prediction a day before, had said that it expects a ‘below normal’ monsoon.
Skymet’s vice-president Mahesh Palawat, in a Twitter exchange on Tuesday, said normal rainfall in a monsoon season is defined as the country receiving 96% to 104% of its average rainfall. The IMD said it expects a 96% probability of the country’s long period average (LPA) rains this year, while Skymet put its predictions at 94% of the LPA this year for the monsoon period between June and September 30.
"The IMD picked 96%, which is at the lower end of the normal rainfall prediction range while we at Skymet put this figure at 94 percent. Though the difference appears to be very small, the significance on the ground level between a normal monsoon season and a below normal monsoon season can be very different," Palawat explained.
The sea surface temperatures over the equatorial Pacific Ocean are rising and with this, Trade Winds from east to west die down or become weak. This results in weaker monsoon winds impacting the South West Monsoon. “Data from the past 50 years, shows that in 60 % of these years when El Nino conditions developed, the South West Monsoon was below normal. This is the reason why we went with a below normal prediction,” Palawat said.
He said El Nino conditions will begin developing in June which will probably see the timely onset and progress of monsoon over the country with the initial spells of rain falling in the normal category. But the second half of the monsoon season will be impacted, he added.
