The Northeast Monsoon season makes an appearance after Southwest Monsoon bids adieu to the country. Usually, Northeast Monsoon arrives during the third week of October. Northeast Monsoon pertains to five divisions of Southern Peninsula including Coastal Andhra Pradesh, Rayalaseema, South Interior Karnataka, Tamil Nadu as well as Kerala.
The maximum rainfall is observed in the state of Kerala throughout the season while most amount of rains are seen in the month of October. Not only this, October happens to be the rainiest month for all the five regions of Peninsular India. November sees slightly lesser rainfall while the least amount of showers are witnessed in the month of December.
Talking about Tamil Nadu, the state is the biggest beneficiary in terms of rains during this season, as rainfall activity is quite less in the Southwest Monsoon season due to it lying in the rain shadow area. Northeast Monsoon is the first to set in over the state of Tamil Nadu while the last to withdraw from this region.
Given below is the table for rain amounts for all five divisions observed during Northeast Monsoon season
Northeast Monsoon sees very high variability both intra and inter-seasonal. The co-efficiency of variation in the season is about 27 percent which means that +/-27 percent of rains during each season is considered to be as normal.
In fact, the normal range is +/-11 percent which means normal rainfall is between 89 and 111 percent. Huge surplus as well as deficits are also seen during this season.
In the last few years, there have been varied rain amounts in the Northeast Monsoon season with 2017 witnessing 86 percent of rains, 2016 seeing very little rains at a mere 35 percent, 2015 recorded a whopping 132 percent of rainfall, rains were at 88 percent in 2014, 86 percent in 2013, 93 percent in 2012, 96 percent in 2011 and a massive 154 percent in 2010.
In contrary to the Southwest Monsoon which sees more rains in La Nina and lesser in El Nino, rainfall activity during the Northeast Monsoon season is higher during the El Nino and very less in La Nina.
Image Credit: wikipedia
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