As Agni Nakshathiram 2017 winds down, today being the last day, heat quotient is set to be pushed up a notch over North Tamil Nadu under the influence of the Bay disturbance under the influence of the Well Marked Low Pressure which is expected to become a Depression in the next 12 – 24 hours or so. Numerical Models are fairly consistent on a Northerly track for this disturbance on its way to making landfall in Bangladesh about 48 to 72 hours from now.
In the meanwhile Southwest Monsoon has advanced over parts of Sri Lanka and Comorin areas as well with further advance expected over the Bay arm in the next couple of days under the influence of the above mentioned Bay disturbance. IMD has also confirmed Maldives and South Kerala is in line for a monsoon onset around 30 / 31st May as per schedule along with Northeastern states of Nagaland, Mizoram, Manipur & Tripura.
In the meanwhile the heat quotient for Tamil Nadu will go up a notch particularly in North Tamil Nadu under the influence of the strong Westerlies which have been streamlined due to the presence of the Bay disturbance. Numerical Models indicate North Tamil Nadu could see day time maximum temperatures to stay about 2 – 4 degrees above normal. While indications do not point at a repeat of temperatures seen during the 3rd week of May Chennai could see temperatures stay above 40 at both observatories in all probability
Places like Vellore, Tiruvallur could also see fairly high day time temperatures while oppressive conditions could persist over large parts of Kanchipuram, Tiruvannamalai & Villupuram districts as well in North Tamil Nadu. Numerical Models indicate parts of South TN around Madurai & Virudhunagar districts could see day time temperatures to be around 4 degrees higher than normal.
On the rain front today also could be a quieter day for most parts of Tamil Nadu with isolated rains on the cards in a few areas of North TN and around Madurai, Dindigul districts of South TN. Some models indicate a fairly active spell of rains for North Coastal TN slightly to the south of Chennai though we need to see if it materializes as drier atmospheric conditions is expected to prevail.