In the early sixties I lived in Tracy, CA, not far from Sacramento but away from major heat islands. At that time it was common for summer temperatures not to dip below 105 degrees at night for three or four days at a time, temps in the tomato fields routinely went up into the 120s, and the humidity was sickeningly bad (from all the irrigation canals, it was claimed). I seriously doubt that this summer is worse than that of 1961 or 1962, but of course, it isn't over until the fat lady sighs and dies.