The last few days days have seen most of Tamil Nadu record slightly above normal temperatures during the nights thanks to the presence of the Trough of Low off the coast of Tamil Nadu & Andhra Pradesh bringing the surface level winds from the sea moderating the night time temperatures. Both the Chennai Observatories recorded 1 degree more than normal yesterday while even a place like Vellore which sees sub 20°C at this time of the year recorded 21°C.
Numerical Models though are indicating starting tonight most of Tamil Nadu to see night time temperatures stay slightly below normal with possibly Sunday being the coolest in the current spell. While for coastal areas it may be touch and go tonight interior areas for sure will see the temperatures in the night dip by a couple of degrees compared to the last few days
The last few days saw a weak disturbance in Bay influence the conditions over Peninsular India. This is bound to change as the High Pressure Area is expected to slide down south towards Peninsular India thereby creating a diurnal High Pressure Zone over South India. Aided by more clearer skies than the past few days we can expect the night time temperatures to drop with interiors getting back to their cold nights once again.