Pradeep informs us :"Historic Rains comes to end. 30000 cusecs released from Poondi and 29000 cusecs released from Chembarabakkam"
The formation of the Vortex has weakened, or rather it has to an extent merged in the trough. The Vortex normally remains stagnant as explained earlier.
But, some charters prefer to show the formation as a Low (shown in a chart yesterday on this site).
With a rigid High pressure ridge in the North of the formation, and obstructing the trough, the whole system was "blocked " from moving North. The anti cyclone (again) played a part in the prolonged rainfall over Chennai
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