Sunlight was a luxury in Calcutta on Thursday as an overcast sky and spells of rain here and there kept the chill feel intact. The sky is expected to clear up from Friday second half and the Celsius should go downhill, the Met office has said.

Some private forecasters predicted that the mercury would drop below 10 degrees on Friday. A conservative forecast from the regional Met office in Alipore said the minimum temperature was expected to hover between 12 and 13 degrees.

The minimum temperature went a notch above normal to 15.7 degrees on Thursday. But the woollens were on because the Celsius did not go above 20.3 degrees. The dip in day temperature — it was around 18.5 degrees at 2.30pm — meant the chill was felt throughout the day.

The Met office in Alipore recorded 1.5mm of rain till 8.30pm on Thursday. The intensity of the showers was more in New Market, Dum Dum and Cossipore, according to the Calcutta Municipal Corporation.

The cricket coaching camps by the Rabindra Sarobar had fewer trainees than usual in the afternoon.

A trough of low pressure stretching from north Bengal to Odisha is behind Thursday’s cloud cover and light rain. The system, which was over Jharkhand and Chhattisgarh a day before and moving eastwards, is expected to lose steam and dissipate over the next 24 hours.

Despite not being directly over Calcutta, the system made its impact felt. The sky was overcast for most of the first half.

The sun made a brief appearance before quickly retreating behind the clouds.

Several pockets of the city such as Cossipore, Ultadanga, Ballygunge and Esplanade got around 1.5mm of rain in the evening, said the weather office. The Met office in Alipore recorded “traces” of rain.

“The minimum temperature went up because the northwesterly winds were blocked by high moisture content in the air. The cloud cover ensured the sun remained hidden and led to a dip in day temperature,” said Ganesh Kumar Das, director, India Meteorological Department, Calcutta.

Friday’s first half is likely to be foggy and then cloudy in Calcutta. The sky may clear up later, making way for the free flow of cold winds from northern India.

“The minimum temperature is likely to go down up to three notches in the next 48 hours,” said a Met official.