This year could be the UK's warmest as measured by the world's oldest temperature record over almost 250 years, say researchers.
The 11 months from January to November have already been the warmest period on the Central England Temperature record.
And meteorologists from the University of Reading believe there is a 75% chance the year will turn out to be the hottest since the record began in 1772.
They say man-made climate change is at least partly to blame globally.
According to the CET record - which measures representative temperatures from a triangular area between Lancashire, London and Bristol - every month so far this year apart from August has been above the long-term average.
The researchers said 2014 would set a new record unless December temperatures were cool.
BBC News environment analyst Roger Harrabin said it had been a "year of weird weather".
"A record wet winter with floods to match. Then the driest ever September, followed by the Halloween heat - the warmest such day on record," our correspondent said.
November in Australia was its hottest ever, contributing to its hottest ever spring.
Global and UK figures are due to be published by the Met Office later.