Southwest Monsoon has been subdued over Tamil Nadu for the last few days. But now, we can expect light to moderate rainfall over many parts of the state, particularly over North and Central districts.
At present there is a low pressure area over Westcentral Bay of Bengal. We can see a trough extending from this system up to Tamil Nadu. This trough will be responsible for scattered rains in Tamil Nadu for next 48 hours.
Monsoon 2015 in Tamil Nadu
Tamil Nadu lies in the rain shadow area and receives major amount of rainfall during the Northeast Monsoon season, which lasts from October to December. Southwesterly winds bring heavy rainfall over Kerala and South Interior Karnataka. By the time these winds enter Tamil Nadu, they get deflected and become devoid of moisture.
This year the state has received on and off good rains during the Southwest Monsoon season as well. Even with the El Nino threat looming large, the performance of Monsoon in the state has been normal so far.
This season Tamil Nadu witnessed large variations in Monsoon rains. In the month of June, the country received 16% surplus rainfall and the state received 36% more rainfall than the normal average.
This excess rain got consumed by the middle of July and the state went on to record deficit rains to the tune of 9%. The rainfall deficiency in Tamil Nadu rose to 15% by July 21. With some good showers during the last few days of July, rainfall deficiency came down to 7%. First few days of August has seen some good rains as well, bringing down the deficiency in Tamil Nadu to 5%. With subdued rainfall thereafter, the Monsoon rain deficiency rose to 15% by August 15.
Southwest Monsoon remained vigorous over the state on August 16. Rains continued the next day as well and the state witnessed five times more Monsoon rains than the normal average for the day.
As of August 25, the cumulative rainfall figure stands at a surplus of 1%. According to Skymet, August will end on a good note for Tamil Nadu and the Monsoon rains will remain in the normal range.
Image credit - The Hindu
