Private weather analyst Hemachandran has predicted that there is a possibility of 500 mm of rainfall in a single day along Tamil Nadu’s coast.
Regarding this, Hemachandran, known as the Delta Weatherman, posted on his X account about the northeast monsoon.
In it, he stated:
This year in the northeast monsoon, will it be a severe drought or a major flood?
“Due to the impact of Super El Niño, the weak southwest monsoon, the summer heat that will continue until October, and water bodies drying up and falling under the grip of drought, farmers and the public in Tamil Nadu are waiting in anticipation for the northeast monsoon.
“This year, as much as 500 mm of rainfall could occur in a single day along Tamil Nadu’s coast…” Most people think El Niño will bring only drought. But globally, El Niño can cause drought 70 percent of the time and excessive rainfall 30 percent of the time. At present, we are seeing drought conditions and the impact of the heat in Tamil Nadu.
This situation will gradually ease from the first week of October. After that, from October 15 onward, during the northeast monsoon period, Tamil Nadu will record rainfall far above normal.
In Tamil Nadu, El Niño has a three-stage impact. Already, the first stage has brought below-normal southwest monsoon rainfall, resulting in insufficient water storage in water bodies and a prolonged summer. This will continue until October.
After this, from Oct. 15, the easterly winds will arrive, and from Oct. 20 to Dec. 20, the second stage of impact will occur. That will be exactly the opposite of what has been happening now. In other words, it will bring good rainfall. In particular, it will cause rainfall above normal and extremely heavy rain in a short period of time.
The third phase of impact will last from January to July next year. This is when the heat wave and rising temperatures will occur.
At present, the temperature in the central Pacific Ocean has risen by 3 degrees Celsius above normal. In the eastern Pacific Ocean, it has risen by 5 degrees Celsius. This temperature will increase further in the coming days.
Therefore, an extremely intense super El Niño, unlike anything the world has seen so far, is expected to form in November this year and last until January 2027.
Similarly, at present in the Indian Ocean region, lower-than-normal temperatures are being recorded in the eastern Indian Ocean, and higher-than-normal temperatures in the western Indian Ocean.
We classify this as a “positive IOD.” This positive IOD has remained at 0.65 degrees for the past three weeks and has now changed to 0.71 and 0.75 degrees Celsius. It is predicted to increase to 1.2 degrees in early November.
As a result, ocean-related oscillations will become favorable for the Indian Ocean. This will turn into a stationary oscillation in one place and bring rainfall. In particular, higher-than-normal humidity and wind convergence will develop, producing extremely heavy rainfall in a short period of time.
Generally, during the northeast monsoon season, Tamil Nadu receives rainfall as low-pressure areas, deep depressions, and cyclones form. This year too, the same is likely to happen.
In particular, there is a possibility that one cyclone each may form in the Bay of Bengal and the Arabian Sea this year. This cyclone is likely to bring heavy rainfall and will not cause wind damage. Subsequently, weak disturbances such as wind circulations and low-pressure areas will form one after another. This will be favorable for the entire state of Tamil Nadu.
From October through December, Tamil Nadu would normally receive 440 mm of rainfall over these three months. However, this year there is a chance it may receive around 500 to 600 mm or more of rainfall.
In this, not only Tamil Nadu’s coastal districts but also the inland districts and western districts are all set to receive good rainfall.
In particular, rainfall above normal is expected to be recorded in coastal districts including Chennai, Tiruvallur, Chengalpattu, Cuddalore, Mayiladuthurai, Nagapattinam, Tiruvarur, Thanjavur, Ramanathapuram, Thoothukudi, and Tirunelveli,” he noted.