The Celsius plunged to 12.1 degrees in Kolkata on Monday, the lowest so far this season.
It was two notches below normal. The Met office has predicted a further dip on Tuesday.
Kolkatans spent another day shivering as the maximum temperature also stayed below 20 degrees. At 19.8 degrees Celsius, it was six notches below normal.
The readings meant the early hours of Monday saw a biting chill and the rest of the day was consistently cold.
Sunday was gloomy and overcast in Kolkata, with some places in and around the city receiving drizzles. The Met office had predicted a chilly, foggy and cloudy Monday.
The chill was there but the fog had weakened considerably. The sky was also not as cloudy as predicted.
"Kolkata did not get much rain. But Jharkhand and Odisha did. So did some districts in south Bengal. The showers helped in clearing the fog. A large chunk of the clouds moved towards the Bay of Bengal," said G.K. Das, director, India Meteorological Department, Kolkata.
"As a result, the northwesterly winds got a passage to south Bengal and dragged the Celsius down. The fall in the night temperature was because of the dry and cold northwesterly winds. The low day temperature is linked to the strong winds and the remnants of the clouds and fog," he said.
Monday was sunny in parts. But the sun was milder than usual.
A high-pressure zone over the Bay has also changed its position. “The high-pressure zone was over the north Bay. It has descended to west-central Bay. The system, in its earlier position, was sending moisture into Odisha and parts of south Bengal," said Das.
"The strong northwesterly winds are expected to drag the minimum temperature further down," said Das.
But the minimum is expected to start rising from Wednesday, the Met office said. The high-pressure zone is expected to come up again. A cyclonic circulation is also expected to take shape over Chhattisgarh.
"Kolkata might get some rain on January 24. The two systems are likely to keep the city cloudy till January 26," said Das.
Once the two systems weaken, the northwesterly winds are expected to make a comeback. The days are likely to be much warmer, starting January 27.
