Chennai got 14cm excess rain between June 1 & September 1 – Times of India

CHENNAI: The city and its suburbs may be less dependent on the upcoming northeast monsoon, or ‘retreating’ monsoon, as the Nungambakkam weather station, which covers the core areas, has reached its June-September target one month before the season ends.
The city weather station has from June 1 to September 1 recorded 465.8mm, an excess of 144.7mm over the normal of 321.1mm. During the same period, Meenambakkam weather station, which covers the southern suburbs, recorded 384.8mm, a surplus of 29.4mm over the normal of 355.4mm. The average rainfall for the June-September season for Nungambakkam is 440mm and 480mm for Meenambakkam.

N Puviarasan, director of the Area Cyclone Warning Centre under the IMD (India Meteorological Department), said the current rainfall activity in the city and state was due to the weak southwest monsoon currents creating favourable conditions for convective activity. Weak westerly winds allowed the entry of easterlies leading to convergence and convective closer to the coast. “Unlike last year, when the southwest monsoon brought good rainfall in states like Kerala and the Western Ghats, this year, the rainfall in Kerala in June and July has been deficient. August too did not see much rain. That was why we had been seeing rainfall in Tamil Nadu,” he said. “We have forecast rain for Chennai and suburbs for the coming days too.”
Of Chennai’s average annual rainfall of 1,383.9mm, the June-September season accounts for 431mm, while the northeast monsoon, which runs from October to December, brings 867.4mm.
But since June 1, Chennai subdivision, which covers other rain gauges in the city, registered 379.2mm against a normal of 335.2mm, a surplus of 13%; Kancheepuram 383.6 against a normal 336.4mm, a surplus of 14%. Tiruvallur, which has reservoirs supplying drinking water to the city, recorded 466.7mm against an average 325.4mm, which is a surplus of 43%; and Chengalpet registered a deficit of 9% with 296.2mm, against a normal of 325.4mm.
Blogger Pradeep John said conditions look favourable for rainfall in Chennai and neighbouring districts in September as well. “We can expect rainfall between September 1 and 4 before a low pressure forms closer to north Andhra Pradesh. There are more such days during the month for rain both in Chennai and north TN,” he said.