The MIA winter is finally set to make an entry.
The Met forecast came after one of the rainiest December days in Calcutta in recent years.
The showers were triggered by the remnant of Cyclone Michaung that moved inland after making landfall in Andhra Pradesh on Tuesday.
The overcast conditions dragged the day temperature down so much that the gap between the maximum and minimum temperatures was negligible. The minimum was on the higher side because the moisture stalled the flow of the northwesterly winds.
Many Calcuttans had to put on an additional layer of clothing because much of the day had more than a hint of chill.
Metro takes a closer look at what caused the showers and what lies ahead.
Celsius
As the remnants of Cyclone Michaung dissipate, the northwesterly winds will start blowing into Calcutta and usher in the chill that the city has missed this season.
The minimum temperature is likely to slide to around 16-17 degrees by Monday.
The weather in Calcutta will improve from Friday but the sky is likely to be partially cloudy. “From Saturday, the sky will be clear. The moisture content will reduce significantly, paving the way for the return of northwesterly winds from Kashmir, which is now under a cold spell,” a Met official said.
The weather office recorded a maximum temperature of 21.1 degrees Celsius in Alipore on Thursday. It was seven notches below normal.
The minimum was 19.9, three notches above normal.
In contrast, the maximum and minimum temperatures were around 29 degrees and 22 degrees on Monday, when Michaung was raging on the Bay.
“The gap between the two was minimal because the day temperature was much lower than usual for the better part of the day (Thursday). That is why people felt cold, despite the missing northwesterly winds,” said a Met official.
By Thursday afternoon, the remnants of Michaung had reached “south Chhattisgarh and adjoining Vidarbha region” as a cyclonic circulation.
Rainy Thursday
The showers in Calcutta started on Wednesday evening. By that time, Michaung had moved to south Odisha as a low-pressure area.
The light showers continued late into the night. But from Thursday morning, the volume and spread went up. Till late afternoon, the rain was almost non-stop. The intensity was on the lower side, occasionally going up. But the showers were persistent.
Around 1.30pm, the top of The 42, the tallest residential building in Calcutta, was almost invisible because of the cloud cover.
Between 8.30am and 8.30pm, the Met office recorded around 25mm of rain in Alipore. But most of the rain came between early morning and afternoon. Between 8.30pm on Wednesday and 8.30pm on Thursday, the volume was around 32mm in Alipore.
Ballygunge was among the wettest areas in Calcutta, recording 41mm of rain till 2pm. Maniktala got 32mm and Mominpore 29mm.
Thursday was among the rainiest December days in Calcutta in recent years, according to Met records. On December 6, 2021, the city (Alipore) had received 74.5mm of rain. On December 19, 2018, the city got 26mm.
“In addition to the cyclonic circulation (remnant of Michaung), there was a trough of low pressure from south Chhattisgarh to Bangladesh. The circulation and the trough sent a heavy volume of clouds and southeasterly winds to Calcutta. That caused the rain,” said G.K. Das, director, IMD, Calcutta.