In what could be the parting spell of NEM2019 the next couple of days could give an opportunity for some of those places to reduce the deficit as Easterlies are seen strengthening up to North Tamil Nadu latitude. It appears as though Nature may want to reduce the deficit as much as possible before taking the monsoon to Southern Hemisphere.
Under normal context during Northeast Monsoon time we look for synoptic disturbances over Bay of Bengal to enhance the rainfall prospects for Tamil Nadu. This time around though Bay remains subdued the incoming Western Disturbance could play the role of Rainfall Enhancer. Mid Latitude Trough is seen dipping upto Peninsular India is likely to provide good atmospheric conditions for the Easterly driven rains to amplify over parts of Tamil Nadu.
While most parts of Tamil Nadu are likely to benefit from this spell of rains, coastal areas are likely to be the biggest beneficiaries as usual from Easterly driven rains. In particular the stretch between Marakkanam to Delta could see heavy rains at a few places due to wind confluence from the East. Pondicherry, Karaikal & Parangipettai along with Chennai are the only coastal stations under deficit for the NEM season as things stand. This upcoming spell in all probability will wipe out the deficit for all places except Nungambakkam observatory.
All in all a good strong parting spell likely from NEM2019. Chennai will see rains return later in the evening / night with few parts of the city especially the southern suburbs likely to see heavy spells at times during the morning hours.