Has the southwest monsoon set in over India or not?
The India Meteorological Department (IMD) declared the advent of the southwest monsoon on Sunday (May 29), sparking controversy with top government officials questioning whether the set norms for such a declaration were followed, The Hindu Business Line reported. Skymet, a private weather forecaster, has also alleged that the IMD declared the arrival of the monsoon in "haste," ignoring the well-established norms and criteria "blatantly."
Why does this story matter?
Officials believe the IMD made the declaration because it had previously stated that the monsoon would arrive on May 27. However, the monsoon's progress was halted last week due to the negative Indian Ocean Dipole (IOD). The actions of the weather agency are now being scrutinized at the highest levels in New Delhi. "IMD is being criticized... It has embarrassed all," an official stated.
Skymet's statement over the controversy
"Declaring monsoon based [on] a single-day observation (May 29) amounts to a gross violation of standards, never attempted in the past. Any repute scientific body can ill afford to bend rules and criteria, just to prove the forecast right," Skymet stated. "Such a step, if taken knowingly, becomes highly objectionable and if otherwise, amounts to an illusion of knowledge (sic)," it added.
What are objective criteria to declare monsoon?
The monsoon's arrival has established objective criteria like rainfall, winds, and outgoing long-wave radiation (OLR). If, after May 10, 60% of the provided 13 stations in Kerala, besides Mangaluru, have confirmed 2.5mm or more rainfall for two successive days, the onset of monsoon over Kerala can be declared on the second day, provided the winds and OLR criteria "remain in concurrence," reported Business Line.
How were objective criteria violated by IMD?
While alleging the IMD has violated established criteria, Skymet stated, "The most important and visible manifestation of rainfall (w.r.t. monsoon) fell short on May 28 and May 30. The onset conditions were fulfilled only for one day, May 29." "The day prior (May 28) and a day later (May 30), merely less than 40% of the designated stations met the rainfall criteria," Skymet added.
7 of 14 earmarked stations received no rain: Skymet
The monsoon doesn't "seem to be kicking up soon over Kerala and peninsular India," said Skymet, also noting that on May 30, seven of the 14 required stations received no rain and two others witnessed less than 1mm rainfall. "At best, Northeast India is well within norms for announcing...monsoon. Most areas of Tamil Nadu, Karnataka, Kerala, and Rayalaseema will have to wait," it added.
What is the latest IMD prediction?
Meanwhile, the IMD, on its part, has predicted widespread light/moderate rainfall with thunderstorms over Kerala, Mahe, and Lakshadweep over the next five days. Isolated/scattered rainfall is expected over Andhra Pradesh, Telangana, Karnataka, Tamil Nadu, Puducherry, and Karaikal. Squally weather is expected over the next five days in the southwest and the southeast Arabian Sea, Lakshadweep, and along the Kerala coast, as per the IMD.
