Due to dry northerlies & moisture filled easterlies interaction South delta places like Vedaranyam & surroundings received cloud burst kind of intense heavy rains during yesterday between 15:00 and 17:00 hrs. It has recorded nearly 15 cms just in 2 hrs time frame. Cumulative last 24 hrs total stands around 19 cms.
We have been warning the public and government officials since the first week of September that there is a “short period of intense rains & excessive rainfall chances there at North coastal & Delta districts during this November and December.” Rainfall was typical up until now, but when planetary waves like the Madden Julian Oscillation and Equatorial Rossby has begin to affect the East Indian Ocean, the peak rainfall episodes are not far away.
For next 48 hrs, dry northerlies & moisture filled easterlies convergence likely to bring widespread heavy to very heavy rains to delta districts & parts of south coastal Tamilnadu like “Mayiladuthurai, Karaikal, Nagapattinam, Thiruvarur , Thanjavur (south coastal) and Rameshwaram, Pamban, Thuthucorin dts“. Isolated coastal places of the above mentioned districts likely to see Intense rains at short period of time (2-3 hrs time frame).
The fierce conflict between dry northerlies and moisture-filled easterlies is the cause of these rains. As a result, when the dry northerlies take over, there will be a lull, and when the easterlies pick up speed, there will be brief, heavy downpours.
Chennai to Cuddalore zone likely to see break monsoon conditions & typical fog/mist activity for next 5-6 days. Rains are expected to return for North coastal Tamilnadu from 23rd November, and Third round of Northeast monsoon 2024 likely to be vigorous between Nov 25th and 30th, 2024. Following that, we likely to see Fourth round of rains during Dec 1st week it self. Especially Chennai, Thiruvallur, Kanchipuram, Chengalpet, Villupuram, Cuddalore, Mayiladuthurai, Karaikal, Nagapattinam, Thiruvarur and Thanjavur dts should be a hot spot region of 3rd & 4th round of rains between Nov 25th and Dec 5th, 2024.
Hence, with the influence of favourable planetary waves, atmospheric and oceanic parameters North coastal Tamilnadu & delta region should be ready to see this kind of short time intense rainfall activity & extreme rainfall activity during next 3-4 weeks time frame.
