Somethings never change in life is a very popular sentiment. This has been used by banks on many occasions to communicate to customers. The most famous instance of a financial institution using this sentiment was MasterCard running the “Priceless” Campaign. There are somethings money can’t but for everything else there’s a MasterCard. Similarly summer is something we cannot avoid even if we wish too. When dry weather conditions prevail it makes things worse.
The last couple of days in a way showcased what is in store for the next couple of weeks for Tamil Nadu. The development of convective thunderstorms during the evening hours to an extent mitigated the afternoon heat. On Thursday Erode became the 3rd IMD observatory in TN to touch the 40°C mark for the year. Vellore and Madurai AP were the first two stations to record 40°C during the first round of active summer. On Saturday Tiruttani became the 4th station in TN to record 40°C mark for the year. During this 2nd round of active summer conditions Cuddalore, Trichy and both the Chennai observatories also recorded the hottest days of the year.
The second round of summer had a solace in the form of thunderstorms which brought good rains to the interior areas. Both operational and sub seasonal weather outlooks indicate a period of dry weather ahead for Peninsular India. Except for places along the Ghats which may benefit from thunderstorms rest of the region is expected to see mostly dry weather. This spell of dry weather is likely to enhance the summer heat quotient as well. Sub seasonal weather outlooks indicate over the next couple of weeks most parts of Tamil Nadu may see anomalously hot weather conditions.
Also the overall atmospheric conditions may become suppressive with Kelvin wave moving further East in the coming days. The presence of Kelvin enhanced thunderstorms over the past few days though the trigger was wind discontinuity. With the absence of favourable tropical waves we may see dry weather firmly established. By last week of April parts fo North TN may see afternoon temperatures stay 3 or 4°C above normal.
Last week saw the development of a Well Marked Low in Bay of Bengal. This triggered weak westerlies which increased the heat over Peninsular East Coast. Weather models indicate Easterlies may not return back to strength from now on with gradually westerlies establishing over Peninsular India. This effectiveliy would make North TN, adjoining Coastal AP and Rayalaseema region the hottest areas in Peninsular India.
All in all a period of dry weather is likely to prevail. This is likely to enhance the summer heat for parts of Rayalaseema, Coastal AP and North TN. On days when sea breeze is benevolent Chennai and suburbs may escape. The days whe sea breeze remains weak suburbs of Chennai may bear the brunt of afternoon heat.