SWM is still prevalent in lower latitude.[i.e below 21 Deg North]. The less strengthen SWM winds at upper level form a UAC near Srilanka.
 This UAC is pumping easterlies in to TN region.
 This may lead to a formation of low in SE bay.
 This is expected to give copious rainfall down south TN.
 Two anticyclones along 22 or 21 Deg North latitude one in the west end and other in the far east end of India is creeping. up
 This may lead to simultaneous withdrawal of SWM and onset of NEM by 22 or 23 Oct 2013.