Near constant bombing of Japan started in November 1944 with the fall of Saipan and Tinian to the USA. The first B-29 targets were industrial factories in Tokyo, Osaka, Nagoya mainly. High altitude precision bombing was not effective, but Japanese citizens in large cities certainly knew things were starting to go badly
Things turned much worse for urban Japanese starting in February 1945 when Curtis LeMay began low-level (more accurate), concentrated firebombing of major Japanese cities. In the most devastating firebombing raid of March 9-10, 16 square KM of Tokyo was destroyed, and 100,000 killed. The average Japanese in major cities certainly knew from experience at that point they were in deep trouble.
“Things turned much worse for urban Japanese starting in February 1945 when Curtis LeMay began low-level (more accurate), concentrated firebombing of major Japanese cities.”
I was surprised to learn that the bomb sighting was useless for high level bombing due to the air currents over Japan.
Low level bombing was the best way to be accurate with the bomb load.
It didn’t hurt that many houses in Japan were traditional bamboo and burned to the ground in minutes.