The threat of a cyclone and chances of tropical storm have been looming large for the last few days. A well marked low pressure area is now lying over extreme outer region of Southwest Bay of Bengal (BoB) and equatorial region. The low pressure is centered around 4.5°N and 83.5°E, far to the south and more than 800km away from the capital city Chennai. It is likely to become a depression soon and be a deep depression in the next 36-48 hours. There are formative circular cloud bands around the broad low level cyclonic circulation. But, these seem to be fragmented partially in some of the sectors. The vertical wind shear is moderate to high and does not support rapid strengthening of system. However, the sea surface temperature is quite high( 29°-30°C), and carry adequate heat potential for sustenance and growth of the system. The low pressure is currently located in the equatorial region where, it lacks Coriolis Force, very essential for intensification. As the system moves further westward, terrain effect and the associated friction may deter any explosive strengthening. Even, the entrainment of dry air negates sharpening of the weather systems.
There is no consensus among the various models on the likely track, timelines and intensity of the weather system. The potential for development of a significant tropical storm in the next 24 hours remains medium. The confidence of forecast for the tropical cyclone in the next 48 hours remains low. The favourable conditions getting offset by the rescinding factors, leave the system in a lurch for any clear verdict. Though, the depression will come too close to the coast by then, but observation period of another 24 hours becomes imperative.
Notwithstanding the ultimate fate of the system, short notice preparedness is the key to avert and tackle the contingencies. Irrespective of the grade of the storm, inclement weather conditions are likely for Tamil Nadu , Puducherry, Karaikal and South Coastal Andhra Pradesh. It may disrupt the communication and connectivity, albeit not for longer duration. Heavy rains may impact and throw the normal life out of gear. All precautionary measures need to be initiated, including moving people to safe shelters.