Check heat risk by postcode. The UK recorded 40.3°C in July 2022 - the highest temperature in national records. LocalRisk uses Met Office UKCP18 climate projections to show projected extreme heat days for 1.8 million UK postcodes - alongside flood, air quality and subsidence risk.
Yes. In July 2022, the UK recorded 40.3°C for the first time, triggering the Met Office's first red extreme heat warning. Heat-related deaths in England that summer numbered close to 3,000. Met Office and World Weather Attribution research calculates that the chance of exceeding 40°C is now more than 20 times higher than in the 1960s, and by mid-century, heatwaves are projected to occur every year rather than occasionally.
UKCP18 is the UK Climate Projections dataset from the Met Office Hadley Centre. It models future temperature, rainfall, and sea level under different greenhouse gas scenarios out to 2100. LocalRisk displays the RCP8.5 high-emissions scenario at 12km resolution, showing how many days above 25°C each area of the UK is likely to see in the 2021-2040 near-term period (compared to a 1981-2000 baseline). RCP8.5 represents high-end warming and is the standard scenario used in UK planning and infrastructure guidance.
Southern and south-eastern England face the biggest projected temperature increases. Greater London, the South East, and East Anglia are expected to see the most additional hot days. Dense urban areas can be 2-5°C warmer than surrounding countryside due to the urban heat island effect - which intensifies the risk beyond what regional projections alone capture. Northern Scotland, uplands, and coastal areas face lower absolute risk but will still see meaningful warming compared to historical averages.
Increasingly, yes. Hot, dry summers drive subsidence - UK insurers paid a record £307 million on domestic subsidence in 2025 alone. Overheating in poorly ventilated homes is becoming a concern for buyers, and the forthcoming Future Homes Standard will require new builds to address it. Some lenders are starting to incorporate climate projections into their longer-term risk models.
Operated in England from June to September by the Met Office and UK Health Security Agency, it has four levels: green (no alert), yellow (vulnerable groups at risk), amber (wider health service impacts expected), and red (significant risk to life for the general population). The first red alert was issued during the July 2022 heatwave. Alerts are based on regional daytime and night-time temperature forecasts.
Flats are the most exposed, especially top-floor units and those with communal heating systems that pipe hot water year-round. Research for the Greater London Authority found up to 67.9% of London homes may be at high overheating risk (GLA / CIBSE, 2022). Smaller homes, over-occupied properties, and modern well-insulated buildings without adequate ventilation are also more vulnerable. Ground-floor homes with cross-ventilation tend to cope better.
We display data from the Met Office UKCP18 climate projections - specifically the RCP8.5 high-emissions scenario at 12km resolution - showing the median number of extreme heat days for the 2021-2040 near-term period, compared to a 1981-2000 baseline. Data is at council level and shown as comparative bands across the UK. This is a scenario-based projection from an official UK source, not a weather forecast.
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