The unseasonable warm October is an example of climatic change, according to weather experts, and UK growers should take advantage.

The Met Office claims that the UK is moving toward a more extreme climate, with longer, dryer summers and more severe winters.

A spokesman said: 'We are breaking more records, there will be more extreme weather.' Indeed the weather has been so mild, that walnuts – a crop that requires warm, humid weather conditions – could become a notable UK product.

Karen Russell of Horticulture Research International told The Times: 'Walnuts are popping up all over the South.' She added that farmers were tempted to grub apple orchards in favour of growing the popular nuts.

October 2001 was the warmest October on record with temperatures touching a remarkable 25°C in London during the warmest period of the month.

Weather patterns could see the largest changes for many years, with a shift in the Gulf Stream away from UK shores threatening to deliver cold snowy winters to these isles.