John Lewis sales surged 13.9% to £61.1m in the week to April 14 as wet weather over the Bank Holiday weekend drove footfall to stores.

John Lewis managing director Andy Street said: “The post-Easter week proved to be almost as good as the pre-Easter week to give us a cracking fortnight’s trade.”

Street said that taking into account the timing of Easter against last year, “a truer comparison with the six days following Easter 2011 reveals a 25% advance”.

Street said John Lewis benefited from the “miserable bank holiday weather on Easter Monday which got the week off to a flying start”.

The bellwether also benefitted from the Digital Switchover in London, which boosted technology sales.

19 of John Lewis’ department stores outperformed against last year.

Street said star performance came from the John Lewis at Home stores, with Poole and Croydon maintaining their “outstanding run of form”. The newest at Home store in Chichester “enjoyed a remarkable first full week, with business roughly twice our expectations”.

Reading was the best performing full line department store.

Street described online sales were “eye-catching”.

Street described fashion as “more challenging” in the cool conditions.

Street added: “Attention now turns to opening John Lewis at home in Newbury today, and then to the summer events.

“With London 2012 Shops open in all our branches and online, and the ‘Celebration of Britain’ products in place, we look well set to capture the nation’s mood.”

Sister chain Waitrose, the upmarket grocer, saw a sales decline of 5.6% due to the six-day trading week for the majority of its branches,  “in contrast to a seven-day trading week last year, meaning comparisons are distorted”.

Waitrose said the comparable six day period gives a more “meaningful” reflection of trade. In those six days, sales were up 4.4%.

The grocer also said comparisons were influenced by last year’s unseasonably warm weather and later fall of Easter.

Food associated with comfort eating sold well in the cooler weather, including casserole and stewing beef, and lamb joints.

Candles and hosiery, which traditionally perform well during cooler weather, also sold strongly.