The monsoon is set to arrive by Wednesday or Thursday, the Met office has said, pinning its hopes on a cyclonic circulation that has defied predictions of making landfall and is still hovering over the Bay.
The Met department has forecast moderate rain in the next 24 hours — which means anything between 2.5mm and 35.5mm. “If the monsoon hits the city tomorrow, the count will be on the higher side,” said a weather scientist.
On Tuesday, the city received 17.6mm of rain.
The monsoon winds usually arrive in the city by June 8 to 10. Despite the delay, Calcutta has so far this month received 113.7mm of rain, resulting from thundershowers.
“A cyclonic circulation on the Myanmar coast is likely to pull the monsoon towards south Bengal by Wednesday or Thursday,” said G.C. Debnath, director, India Meteorological Department, Calcutta.
The circulation had formed over the east-central Bay, raising hopes of the monsoon’s arrival in the city by Tuesday. But the formation veered towards Myanmar and seemed headed for landfall, prompting the Met office to warn of a further delay in the arrival of the rains. “But since the circulation is still over the sea, it’s likely to drag the monsoon to the city in a day or two,” said a weather department official.
A cyclonic circulation, having an atmospheric pressure lower than its surroundings, tends to pull air towards itself.
Tuesday’s showers were caused by thunderclouds that had formed locally because of heat and humidity. The rainfall was not evenly distributed across the city.
So is the rainfall going to be more evenly distributed after the onset of the monsoon? “Not right away. A transitional phase between summer and the rainy season has started and will last for some time even after the arrival of the monsoon,” said Debnath.
On Tuesday, the city’s maximum temperature was 36 degrees, three notches above normal but the lowest the city has experienced for a week.
rain rehearsal before monsoon