Calcutta woke up to possibly its warmest December noon in five decades on Friday, barely 24 hours after breaking a 10-year record.

The Met office recorded a minimum temperature of 22 degrees Celsius, eight degrees above normal and presumed to be the highest since 1951 from when reliable records are available. Thursday’s morning temperature was 20.6 degrees, the highest in a decade.

“I checked the records and found that in 1951, a similar situation prevailed around this period in December when the minimum temperature on December 12 had shot up to 21 degrees. It’s a rare occurrence,” said G.C. Debnath, the director of the weather section at the Regional Meteorological Centre in Alipore.

He said “some more scrutiny” was required to confirm whether Friday’s minimum temperature was the highest in over five decades. The average minimum temperature in the city on December 12 has been 14 degrees Celsius.

The weatherman blames low-pressure systems that block the passage of the North Wind for warm winters. The bad news is that one low-pressure system — called a western disturbance — is being replaced by another over Jammu and Kashmir, from where the cold wind blows towards the plains.

“The western disturbance that formed over Kashmir a few days ago is moving away but a fresh one is likely to form in three to four days. So any drop in temperature will be temporary,” a Met official warned.

With a forecast like that, it isn’t surprising that Calcuttans are feeling a bit under the weather. “I hate this heat. Winter is the time for excursions, picnics and outdoor activities. But December has been so warm this year that I don’t want to step out of home,” said Prithviraj Sengupta, a Class VI student of St Thomas’ School, Kidderpore.

Some schools have postponed their winter programmes because of the warm weather. “We generally issue a circular by the first week of December asking students to come in their winter uniform. We haven’t done so yet this year. We have also postponed our winter camps,” said Seema Sapru, the principal of The Heritage School.

The Australian film team shooting for The Waiting City starring Radha Mitchell and Isabel Lucas has been sweating it out and hoping that things cool down.

The humidity high (97 per cent on Friday) has been the biggest bother, especially for Oscar-winning makeup guru Paul Pattison. “The humidity has been playing around with the makeup quite a bit,” admitted the man who gave Mel Gibson his Braveheart look.

Director Claire McCarthy, who was in Calcutta six winters ago, has been “surprised but not bothered” by the mid-December heat.