Store owners have written off summer after weeks of wet and miserable weather that has killed trade, forcing them to dump shorts and swimwear in the discount bin.

Clothing retailers are experiencing their worst season for at least five years as the wettest June on record left large swaths of the country facing floods and even hailstorms.

Several retailers have rolled out the discount rails earlier than last year, with Debenhams starting its sale two weeks earlier than usual, offering up to 70 per cent off.

Record sunshine in April, which appeared to be a prelude to a baking summer, lulled stores into believing that they would have bumper sales in June and July.

One boss of a high street retailer said: “Everybody wants to get out of this season and move on. It’s tough out there and we are all thinking about next season.”

Underlying sales, which exclude new store openings, are understood to have slumped about 4 per cent in June against the same month last year, even worse than the 3 per cent fall in May. Another high street boss said: “Since we passed Easter the sales have slowed right down. There have been no really strong fashions, the weather has been poor and people have waited for the sales to stock up for their holiday. It’s a combination of weather, economics and fashion.”

The number of shoppers was also down 2.6 per cent in June compared with last year.

The average 5.3in (134.5mm) of rain that fell last month exceeded the previous high of 4.8in (121.2mm) set more than 25 years ago in 1980. “It is a record,” John Hammond, of the Met Office, said.

England, with Yorkshire and parts of the Midlands worst hit by the flooding, passed its 1997 record of 4.8in by more than half an inch with a total of 5.5in (140.2mm).

Northern Ireland had 6.1in (154.5mm), breaking its 5.8in (147mm) record set in 1931. Scotland had the least, with 4.4in (112mm). Wales had more rain than any other part of the country, with 6.7in (170.5mm) falling. Among the highest figures recorded over a 24-hour period for a single weather station was 4.1in (103.1mm) at Fylingdales, North Yorkshire, on June 25.

The floods and heavy rain literally swamped trade in some shops. Yorkshire’s temple of retail, the Meadow-hall shopping centre in Sheffield, remained closed for at least five days after last week’s storms left its ground floor under water.

Some stores in the centre, where water was 7ft deep in places, are not expected to reopen for weeks, and other independent retailers in Sheffield city centre said that they had been visited by only two or three customers on some days last week.

Last year soaring temperatures and the World Cup boosted sales of summer clothing, flat-screen televisions and food and drink.

Retailers listed on the London Stock Exchange have seen their shares drop by about 14 per cent since the start of May. Richard Dodd, a spokesman for the British Retail Consortium, which releases trading figures for June next week, said: “We are expecting weak sales growth partly because of the weather and also because of a sequence of four interest-rate rises.”

Things could get even tougher with the Bank of England almost certain to push rates up to 5.75 per cent today.

Some have asked why was there no advance warning about the rains and floods this summer. The Met Office has had some success in the past with its seasonal predictions but for this summer it predicted a high chance of warmer than normal temperatures, and so far it has been proved right: June was warmer than average, despite all the rain. But the Met Office summer forecast failed to spot anything unusual about the rainfall, and simply ducked the issue.

The art of seasonal forecasts is simply so experimental that we are at the limits of meteorology and computer technology. To make seasonal predictions months in advance, forecasters look at a host of clues from around the globe. This year, a large pool of unusually cool water was picked up off Labrador in the Atlantic, which played a role in our summer temperatures. The Pacific also gave increasing signals from the emergence of La Niña, a big surge of cooler waters across the seas in the Equator that disturbed the tropical atmosphere and had a knock-on effect on our summer.

But all this information tells us little about rainfall, which is much more patchy and localised. The seasonal rain forecasts tend to be drowned out by the bogeyman of forecasters – chaos, the unpredictable swings in weather.The clouds, though, may yet prove to have a silver lining for some. The retail monitor Footfall says that the bad weather and the early sales are luring people back into the shopping centres.

The Met Office forecasts . . .

April 11

70 per cent probability of summer temperatures above average of 14.1C

1 in 8 chance of a repeat of 2003 and 2006 heatwaves

“No indications” of an increased risk of wet or dry summer

“Through the summer we can experience periods of very hot weather”

May 30

High probability of temperatures above long-term average

Rainfall likely to be below average or average for the South

Rainfall likely to be average or above average for the North

“No more than a 1 in 6 chance that summer will be as hot, or hotter, than 2003 or 2006”

June 26

High probability of temperatures above long-term average

Rainfall likely to be average in South, average or above average for the North

Some warm and sunny weather likely but fewer hot and sunny spells than in recent hot summers

What happened

Average June temperature was 13.7C, 1.1C above 1971-2000 average

June was wettest on record with 134.5mm rainfall across UK

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