Next year is likely to be the hottest ever recorded, forecasters have said.
The Met Office warned global temperatures would peak above the record which is expected to be set this year.
If 2016 does prove to be the hottest ever recorded, it would mark the third year in a row in which new records were set.
Experts said the rises were down to a combination of global warming and the natural El Niño phenomenon in the Pacific Ocean.
Met Office research fellow Professor Chris Folland said: "2015 is on track to be the warmest year on record, and this forecast suggests 2016 is likely to be at least as warm, if not warmer."
The average global temperature is expected to be about 0.8C above the worldwide long-term average of 14C around the world.
The Met Office's prediction comes as London basks in unseasonably warm temperatures.
Temperatures in the capital have this week been around double the average of 8C for December.
And the unseasonably mild temperatures are set to remain next week - dashing hopes of a white Christmas for many in the south-east.
The likelihood of the month's current record for the hottest day, 18.3C (64.94F) in 1948, being broken is currently at 4/6, according to Ladbrokes.
It has also put the chances of seeing the hottest Christmas Day of all time at 2/1.
