The figure for 2022 would be announced later.
Since 1884, each of the ten years recording the highest annual temperature have occurred from 2002, according to the forecasting body.
“2022 is going to be the warmest year on record for the UK. While many will remember the summer’s extreme heat, what has been noteworthy this year has been the relatively consistent heat through the year,” said Mark McCarthy, head of the Met Office’s National Climate Information Centre.
Every month except December had been warmer than average, he said.
“The warm year is in line with the genuine impacts we expect as a result of human-induced climate change.
“Although it doesn’t mean every year will be the warmest on record, climate change continues to increase the chances of increasingly warm years over the coming decades,” he added.