It’s the end of June 2026 and temperature records are toppling across Europe. The heat has become unbearable and is proving fatal, with thousands of excess deaths already reported.

In the face of this, climate deniers have been reviving a 2022 conspiracy theory which claimed that weather maps were using more extreme colours to denote temperatures that would have been unexceptional in decades past in order to give the appearance of warming temperatures. As recently as May, the BBC were the latest trusted news source to feel the need to debunk this myth.

A quick glance at the map above looks like something we’d have seen in recent days…but it was created in 1956.

The darkest reds have been applied to denote a mean daily temperature of “Over 62° F” (16.6 °C).

To the south of the UK, the mean temperatures last week were well over this range and, given there is more heat forecast, we could be on for a palette for July 2026 that looks more like the below (generated with ChatGPT), with even more red needed.

The alternative, of course, is to start using hotter temperatures at the lower end of the scale and thus suppress the warming colours. I doubt that would raise much complaint from the climate deniers, but it would offer little reassurance to those who look beyond their weather maps to the direct experience of struggling to sleep and work in such extreme conditions.

If you enjoyed this post then you might also enjoy The Library of Lost Maps. Pick up your copy here.