Northeast monsoon may advance to south interior K'taka

The North East monsoon has set in Tamil Nadu nearly two weeks behind schedule lashing parts of the southern state with copious rain.

Though the sky didn't open up in Chennai, parts of Tiruvallur and Nagapattinam districts and several other parts of the state received rainfall on Friday.

While Nagapattinam got 14 cm rainfall since Thursday night, Karaikal in neighbouring Puducherry received 7 cm rainfall, the weather office said.

India Meteorological Department has predicted “heavy rain likely at isolated places over Tamil Nadu, Puducherry and Kerala” in the next two days.

The conditions are also favourable for the northeast monsoon's march into remaining parts of Tamil Nadu, Kerala, South Interior Karnataka and Rayalaseema region of Andhra Pradesh.

The southern peninsula consisting of five meteorological subdivisions - Tamil Nadu, Coastal Andhra Pradesh, Rayalaseema, Kerala and south interior Karnataka - will receive about 30% of its annual rainfall during the northeast monsoon season between October and December).

Tamil Nadu is the biggest recipient as it generally receives nearly 48% of its annual rainfall during this season. The state is heavily dependent on North East monsoon for irrigation and drinking water purposes.

In the forecast issued on September 29, IMD predicted normal North East monsoon season with 89-111% of the average rainfall expected during the season. According to the forecast the tendency would be towards the positive side of the normal.

The long period average for the northeast monsoon is 332.1 mm based on the rainfall records collected between 1951 and 2000

Specifically for Chennai, the forecast was more than 112% of the LPA, which stood at 438.2 mm for the southern metropolis.

On Friday, IMD officials in Chennai said the northeast monsoon, 2018 might result in surplus rainfall for the state.