Trading at Sainsbury's beat expectations as customers took advantage of the warm weather to buy strawberries at the supermarket and padding pools at Argos.
The group said like-for-like sales, excluding fuel, jumped 2.3% in the first quarter of its year, better than the 1.9% rise forecast by the City.
It said grocery sales lifted 3% in the period as it introduced 250 new summer eating products such as British strawberries, Jersey Royal potatoes and 43 new or improved meals in its Just Cook range.
The group said it was brisk trading at its Argos delivery and collection services which "were particularly popular during the hot weather, when customers wanted products like paddling pools and fans on the day".
The industry has also benefitted from rising prices across the sector this year as the weak pound pushes up imports.
Sales at British supermarkets rose at their fastest rate in five years over the past three months, according to data released by Kantar Worldpanel last week.
Prior to this year the grocery sector had suffered almost three years of falling prices as bargain-hunting shoppers turned to discount rivals, such as Aldi and Lidl.
Chief executive Mike Coupe said the group had "delivered a strong performance".
He added: "The market is competitive and we continue to manage cost price pressures closely. Our strategy is delivering and we are well placed to navigate the external environment."
Earlier this month it was reported that Sainsbury's has entered into exclusive discussions to acquire the convenience store operator Nisa for £130m.
Coupe would not confirm talks had taken place, but added: "A big business like Sainsbury's is always alive to potential opportunities. We have lots of conversations with people all the time."
Sainsbury's bought general retailer Argos for £1.4bn last year.