What: Heatwave-driven changes in shopper behaviour pushed UK retail growth online while weakening in-store sales.

Why it is important: This shift shows how extreme weather is accelerating channel migration and forcing retailers to adapt operations, inventory, and promotions in real time.

UK retail sales maintained modest momentum in June, but the heatwave sharply altered where and how consumers shopped. Total sales rose 1.9% year on year, matching the 12-month average but trailing the 3.1% growth recorded in the same period last year, according to the latest BRC-KPMG retail sales monitor. Online non-food spending was the standout performer, increasing 5.1%, well ahead of both the 1.5% 12-month average and the 2.3% rise seen a year earlier. Online penetration reached 39%, up from 37.7%.
In-store activity was weaker as high temperatures discouraged shopping trips and made retail operations more difficult. Food sales rose 2.8%, below last year’s 4.1% growth and the 3.4% 12-month average, while non-food sales increased 1.2% and in-store food sales fell 1.1%. Demand concentrated around heat-related categories such as fans, air-conditioning units and paddling pools, while gaming and big-ticket purchases struggled. BRC and KPMG executives warned that weather disruption is compounding cost, tax and uncertainty pressures.

IADS Notes: The Retail Week article aligns with recent notionnews coverage showing that weather volatility is becoming a decisive force in retail performance, channel mix, and operational planning. In July 2025, Inside Retail reported that heatwaves and monsoon rains drove shoppers into Korean department stores, boosting footfall and seasonal categories. In September 2025, Retail Week showed that warm and dry weather lifted UK retail sales and redirected demand toward seasonal goods. The opposite effect appeared in February 2026, when Retail Week reported that snow and heavy rain reduced UK footfall and encouraged shoppers toward digital channels. This pattern became more significant against the backdrop of May 2026 reporting from Retail Insight Network on weak physical retail traffic, and June 2026 coverage from Reuters on worsening UK retail demand, cost pressures, and the need for policy clarity. Together, these sources reinforce the current article’s message: extreme weather is no longer a short-term disruption but a strategic factor shaping online growth, store performance, category demand, and retail resilience.

Online sales lead the way in the UK as heatwave keeps customers off the high streets