Supermarket giant Waitrose has reported a surprise increase in certain meals during the heatwaves scorching the UK.

Somewhat surprisingly, sales of winter comfort foods, such as cottage pies, gratins and red wine are on the rise.

The grocer said sales of cottage pies were up 110% while chicken and ham gratin and South African red wine were both up 68% over the last month.

Meanwhile, recipe searches on Waitrose.com for spaghetti bolognese, toad in the hole and mac ‘n’ cheese were up 91%, 67% and 57% respectively.

The results come as fresh heat health alerts have been issued in some areas of England as the fourth heatwave of the year looms.

The supermarket said customers were showing clear signs of “feta fatigue”, bypassing traditional summer salads in favour of cold-weather comfort foods.

Stephen Parkins-Knight, senior innovation chef at Waitrose, said: “Forget the thermostat, when a heatwave goes on, raw salads and chilled plates can often lose their cool fast.

“What we’re seeing is a trend in ‘reverse comfort eating’ – after spending all day drained by the heat, people crave rich, grounding staples to recharge, pivoting back toward comfort and familiarity.

“Think flaky pies, slow-simmered chilli, soul-warming soups, and a bold glass of red.”

The Met Office is forecasting temperatures will reach 29C to 30C widely in the South East on Tuesday, and are expected to peak as high as 35C across southeastern England on Wednesday before easing.

It is the fourth time this summer that temperatures have soared to heatwave levels, with record-breaking temperatures for the month in both May and June and another significant hot spell in mid-July.

July has been 3C above average across the UK, according to provisional Met Office data on the month so far, potentially putting it among the hottest three or four months of July on record.

And southern England has had just 1% of its average July rainfall, while England has had 5% and the UK as a whole 20%, according to the Met Office,

Some spots have gone for weeks without rain – such as Wisley in Surrey which has had 40 consecutive dry days.