Monday, May 23, 2011

Sun's transit of the Pleaides produces rains in Kerala




Rains lashed Trichur at around 0500 AM initiating the rainy Njattuvelas. It normally starts to rain from Karthika Njattuvela onwards and then fierce rains are expected from May 29th onwards when the Sun transits Rohini, Mrigasira, Punarvasu and Pushya.

The heavens are murky now, at about 0900 AM and there is no sign of the Sun. But then rains will accelerate and reach their crescendo during Mrigasira, Aridra, Punarvasu and Pushya Njattuvelas.

The South West Monsoon normally hits the Andamans on May 20th, Bombay on June 10th and Kolkotta on June 8th. This time SW Monsoon seems to be delayed in the Andamans but we expect normal rains this season.

Kerala receives 2500 mm rains every year and about 1500 mm during Kala Varsha or the South West Monsoon. 600 mm during the North East or Thula Varsha and about 400 mm rains during summer grace Kerala, making Kerala a green Paradise !

All have welcomed these rains as it is a big relief from the blistering heat. Yesterday temperature was around 38 degrees and many working under the Sun were cursing the horrific heat. Kerala is situated at about 12 degrees North of the Equator and is known as the Torrid or the Tropical Zone. The climate is never cold. And rains neutrallise the torrid heat of this tropical zone. The entire Malabar coast of 825 kms is graced by the three Monsoons, SW, NE and summer monsoon !

The cold winds from the Indian Ocean should have gone to Madras, but because of the Coriolis Force of the earth, it is deflected onto the Malabar coast. Madras on the other hand do not get the SW Monsoon and has to contend with the North East Monsoon. She receives around 1000 mm of rains from the North East Monsoon, which starts when the Sun enters the First Point of Sidereal Libra ( Thula Varsha ). Unfortunately Madras does not get the benefit of the South West Monsoon !

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