WET PHASE AHEAD: A scene in the city after rain on Wednesday
CHENNAI: The rain is back over the city. Wednesday saw light spells over Aminjikarai, Choolaimedu, Nungambakkam and Ashok Nagar and by 9pm Nungambakkam had registered 14.9mm and Meenambakkam 15.6mm.
Weathermen say that for the next 48 hours, the city can expect overcast skies, intermittent light spells of rain and sudden downpours with thunder and lightning. This is because of a trough or an elongated area of low pressure over the Bay of Bengal. Private forecasters and bloggers said this spell could last at least a week.
India Meterological Department has issued heavy rainfall warning over some places in Chennai, Tiruvallur, Kancheepuram, Chengalpet, Cuddalore, Villupuram, Pudukottai, Thanjavur, Tiruvarur and Nagapattinam. The rainfall will intensify on Thursday because of the presence of a “trough of low at mean sea level overrunning from southwest Bay of Bengal off Sri Lanka coast up to westcentral Bay of Bengal off north Andhra Pradesh and extending up to 1.5km above mean sea level,” the IMD said.
The trough of low brings moisture-laden easterlies from the sea towards the land converging with opposing winds closer to the coast resulting in convective rainfall, weathermen said.
Weather blogger Pradeep John, in his online post, said a pulse from Cyclone Goni, which made a landfall in the Philippines, moved into the Bay later developing into an easterly wave and will be in the form of an inverted trough on Thursday closer to TN coast with an upper air circulation near Sri Lanka.
“The rains will be limited to coastal and south Tamil Nadu till November 13. Winds are converging perfectly over Chennai and surrounding region on November 12 and 13 which will bring heavy rainfall,” he said.
Private forecaster Skymet Weather, in its update, said the spell expected to last till November 16 could be accompanied with lightning, thunderstorm and strong winds that may batter coastal regions, particularly northern Tamil Nadu, rather than the interior areas.