Vets across the UK are reporting heatstroke cases in dogs, cats and other pets that never left home, according to warnings issued as the country entered its third heatwave of 2026. The Guardian reports that animals confined to gardens, carriers and even hutches are presenting with heat injury, complicating a public safety message that has long centred on the hot-car scenario.

Dr Katharine Nelson, director of general practice at the Royal Veterinary College, said the recent run of heatwaves had produced a rise in heatstroke cases among dogs simply resting in gardens or stressed by travel, and among cats confined to carriers The Guardian. Dave Martin, head of welfare at Inspiring Vet Care, described a similar pattern: dogs overheating while lying in direct sun, cats trapped in greenhouses, and rabbits affected by heat while resting in hutches and runs The Guardian.

The scale is quantified in Inspiring Vet Care's own caseload. The group's vets handled 355 suspected heatstroke incidents in 2025, 66% of them during the summer months — a 28% increase on 2024 The Guardian. Nelson noted that heatstroke risk concentrates disproportionately in flat-faced (brachycephalic) breeds, thick-coated breeds, and animals with pre-existing respiratory or cardiac disease — populations whose thermoregulatory reserve is already compromised before ambient stress is added The Guardian. She added that the RVC had even treated a guinea pig for heat stress, a species rarely featured in public heatwave advisories.

The backdrop is a summer of sustained continental heat. Western Europe recorded its hottest June on record, with temperatures reaching 40C or higher in Germany, France and Spain in recent weeks The Guardian. Reuters reported on June 21 that temperatures across Europe were nearing 40C, triggering nationwide warnings and transport disruption Reuters. The human toll has been severe: Reuters reported on June 22 that at least 18 people died in France, including two children who died in a hot car Reuters. Agricultural losses have also mounted — a subsequent Reuters report detailed hundreds of thousands of poultry deaths in France, overwhelming carcass collection services Reuters. France restricted public alcohol consumption during the peak of the heat, AP reported AP, while an earlier AP dispatch in May had already flagged UK temperatures forecast to reach 34C in what was then described as a record-breaking early-season heatwave AP.

Existing welfare guidance has been built largely around the hot-car scenario. The RSPCA's standing advice designates a dog left in a hot car as an emergency requiring an immediate call to police rather than the charity itself RSPCA, and its online materials extend that warning to conservatories and caravans RSPCA. The charity's seasonal summer guidance also addresses flystrike risk in outdoor animals RSPCA, and its equine-specific advice recommends moving horses to shade and pouring large volumes of water over them as emergency first aid for heat exhaustion or heatstroke RSPCA.

The gap between that guidance and the clinical picture now emerging is the notable feature of this reporting cycle. Vet-reported cases cluster around scenarios — a dog dozing in a sunlit garden corner, a cat zipped into a carrier for a short journey, a rabbit left in a run through the afternoon — that fall outside the enclosed-vehicle framework most public messaging still emphasises. For flat-faced breeds in particular, the margin between resting comfortably and entering thermoregulatory failure narrows sharply once ambient temperature and humidity climb, independent of whether the animal is confined to a vehicle at all.

Whether this shifts formal public guidance is not yet established by the available reporting. But the trajectory of the underlying climate data — a record June across western Europe, a third UK heatwave inside a single calendar year, and caseload increases documented year-on-year by clinical providers — suggests the current emphasis on cars alone may understate the range of everyday domestic settings in which pet heatstroke is now occurring.