With Southwest Monsoon 2019 departing from the entire country, Northeast Monsoon rains has finally made an onset over South Peninsula on October 16. Northeast Monsoon is not declared until and unless withdrawal of Southwest Monsoon is completed.
This year, the season has made an early onset, four days before its normal date of October 20. In the last 12 years, it has been only on two occasions that Northeast Monsoon made an early onset. However, it was just by a day or two.
According to weathermen, the super quick withdrawal of Southwest Monsoon and the absence of any Cyclone activity in the Indian seas have paved way for the early onset of Northeast Monsoon 2019.
Moreover, weather models are indicating that Northeast Monsoon is likely to see an active phase for the next two weeks.
Northeast Monsoon is a three-month long season that span from October to December. The Monsoon effects five sub-divisions of the country, namely Tamil Nadu, Kerala, South Interior Karnataka, Rayalaseema and Coastal Andhra Pradesh.
Out of these, the season holds great importance for Tamil Nadu, which records over 50% of its annual rainfall during this time.
Prime criteria for declaring Northeast Monsoon includes the depth of easterlies up to 5000 feet over the Tamil Nadu coast. Also, the onset cannot be declared before October 10 even if the rest conditions are met.
Unlike main Monsoon season, the error margin for the rainfall during Northeast Monsoon is +/- 19%. Since 2010, Monsoon performance has been mostly hanging between normal and above normal rainfall. 2016 and 2018 were the only two years that have recorded deficient rainfall.
Image Credit: NDTV
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