First North East Monsoon Low set to lash Tamil Nadu and South AP

North East Monsoon arrived on Indian shores three days back with not much pomp and pride. Sedate conditions prevailed over most of Coastal Tamilnadu as easterlies blowing offshore was not filled with moisture. But, things are looking North for the NEM, as it will kickstart now in a grand style, courtesy, a low pressure area, which has taken shape over Central Parts of South Bay of Bengal. NEM rains mainly occur due to easterly waves, troughs, low pressure systems including cyclones which move all the way across warm waters of Bay of Bengal, taking steam alongwith it, before it precipitates over Tamilnadu and adjacent South Peninsular region. First rain bearing low of this season is set to move westwards towards TN coasts adjoining Gulf of Mannar in a day or two.

A system in Gulf of Mannar almost always result in widespread rains over TN, as it will streamline easterlies in sumptuous manner towards coasts. Low pressure areas are generally slow moving, moisture rich, which also aids in widespread clouding over its surroundings. As the system hurtles west, rains are set to pick up across coastal Tamil Nadu starting today. Widespread rains will arrive over most of the state from Friday. Rains will occur in multiple spells(at any time of the day over coasts), and it can be heavy at times. The official met agency (IMD) also warns of heavy to very heavy rains to occur in one or two places over TN between 28th and 31st October. Early model estimates are directing the system onto Arabian sea from Gulf of Mannar keeping the rains intact for 3-5 days. We need to wait out for the further course of this first active spell of NEM post Diwali.

Elsewhere across Indian subcontinent, seasonal transition from monsoon to winter is in progress, as dry cool winds from continental Asia started to blow over the region. Cooler nights will be normal going forward in Northern Plains and Deccan Plateau even as the day time temperatures take a dip to seasonal standards. Dry weather is forecast over entire country except over TN, Kerala, South Interior Karnataka, Rayalseema and Coastal Andhra Pradesh.