This becomes even more apparent when you move to cities that are more integrated with local forests in part. You drive by the foresty adjacent area, not even in the forest, and the temperature drops dramatically, easily 5+ C. And as CO2 increases, so too is greenery. [1]
Not only forests but even just tree cover. I live in Berlin and there were a few days a few years ago over 40 degrees, and I remember the difference was stark going from my relatively tree-lined street to an area of the city with only concrete.
[1] - https://science.nasa.gov/earth/climate-change/co2-is-making-...