Over the past few days the Indian Meteorological Department(IMD) has been issuing high-level red and orange alerts for coastal states—Kerala, Tamil Nadu and Puducherry—for what weather experts claim are a 'common phenomenon during this time of the year'.
While such warnings are mandatory and even necessary, the ones being issued this time around by country's official forecaster have led to speculations of an 'overreaction' after the August rain mayhem when the Kerala Chief Minister, Pinayari Vijayan, cited inadequate warning as a reason for widespread destruction in the state.
While the IMD said it had followed the mandated protocol and issued 'rain warnings' well in time, Mr. Vijayan told the state assembly that the rainfall between August 9 and 15 was over three times higher than forecast. In other words, what he implied was that had the state been warned properly, damage to life and property could have been contained.
But so far as current happenings in the Bay of Bengal and Arabian Sea are concerned, meteorologists term them as 'normal and common weather occurrences for this time of the year' unlike the 'exceptional and unprecedented' conditions experienced by Kerala in August.
Weather expert, Mr. Mahesh Palawat says, 'As the direction of the sun starts shifting towards the Southern Hemisphere, sea surface temperatures rise in the Arabian Sea and the Bay of Bengal, resulting in building up of low pressure areas during October and November. Normally, the systems formed in the Arabian Sea move towards the Oman Coast, where SSTs are slightly cooler, causing them to use their reserves.'
“Another reason for the prevailing systems is the MJO (Madden-Julian Oscillation) factor, which is also been providing favourable weather conditions for the enhancement of cyclogenesis in the region”. Unlike a standing pattern like the El Nino Southern Oscillation (ENSO), MJO is a traveling circulation pattern, resulting in rainfall.