Find out more about the data
The heat hazard score for each postcode area was calculated by 4 Earth Intelligence (a satellite analytics company), who measured the average land surface temperature over a sample of days across the past three summers in Great Britain.
Each heat hazard score represents different sized groups, as shown in the scale. This is to highlight the places where the temperature in an area was higher compared to the rest of Great Britain, once the temperature had been adjusted to make it comparable across regions.
For example, a score of one means the postcode was in the lowest 40% of potential heat hazard areas, while a score of five means it was in the top 1% of potential heat hazard areas.
If your postcode is represented by or contains a small square, this may be because your building has too many addresses in it for a single postcode. This block can be shown adjacent to areas with the same postcode, or a few streets away.