Unseasonably warm autumn weather from the United States to Europe is denting sales of heavy sweaters and coats as the critical holiday shopping period approaches, executives at major retailers including H&M said, and some stores are already slashing prices to avoid piles of unsold inventory.

In the past year, clothing retailers have sought to clear excess stock that had piled up due to a shift in consumer demand to essentials from discretionary items like clothing.

But with fourth-quarter temperatures expected to start off warm, according to weather tracking firm Weather Trends International, stores carrying winter styles and gear could find themselves loaded with inventory at the end of the season.