Forecasters had predicted that it could be the mildest December 22 since records began.
Rittle, in Essex, and Great Yarmouth “came close to the record”, while Linton-on-Ouse, in North Yorkshire, achieved a heady 14.7C.
Farmers in Yorkshire’s rhubarb triangle said the mild weather was “very, very worrying”.
They are crying out for a sharp frost to prevent further setbacks to their harvest. Rhubarb plants, which are grown outside, need intense cold so carbohydrates in the roots turn to sugar for the energy needed for forced growing in dimly-lit heated sheds.
Janet Oldroyd Hulme, who grows 1,000 tonnes of forced rhubarb a year at Oldroyd’s Farm in Carlton, Wakefield, said the plants would suffer because they had not been through a dormant period: “It’s very, very worrying – there are people’s livelihoods at risk. We have records that go back to the 1960s and we have never been in this situation. What we need is cold, frosty nights and bright, sunny days, typical English weather, which is what the rhubarb likes as it is a native to Siberia.”
Despite rain and wind crowds gathered at Stonehenge for the winter solstice, the shortest day of the year. Almost 5,000 people were at the Wiltshire landmark for the “very special” time of the latest dawn and the point when the sun is at its lowest in the sky, according to senior Druid King Arthur Pendragon.
He said: “I think we got about 5,000 people in the summer and we were nearly that and it is winter. It has been a very mild December but throughout the night it was rainy and windy which, in turn, might have put some people off.
“I think a lot of people are looking to nature because of global warming and the environment.
“They are turning to Earth-bound religions. The winter is a time of renewal and hope.”
Gardener and horticulturalist Martin Fish, who lives near Thirsk, who has been gardening ever since leaving school 40 years ago, said he had never known a December this mild. Winter flowering shrubs like mahonia and viburnum that would not normally flower until February are out, as is winter honeysuckle. and the lawn is unseasonally lush.
He said: “At this time of the year you expect your lawn to start looking yellowish, but it looks like it does in April in May. It is still growing. I have a lovely Leycesteria ‘Golden Lantern’ which normally loses all its leaves by November but is still in full leaf.”
But he said he wasn’t a fan of the mild weather as lots of plants needed cold periods: “It is also good for killing pests and diseases,” he added.
Meteorologist Emma Sharples from the Met Office said: “It is extremely mild for the time of year and we have seen 16.1C at Rittle, when the daily maximum for December is 7.2C. But we are still some way off the record for the hottest daily maximum, which was 18.3C at Achnashellach in the Highlands on December 2 1948.”