How did the US military bomb Hiroshima?

Hiroshima is sunny and hot. At 7: 09 Hiroshima time, the alarm sounded. Several American planes flew over Hiroshima and circled for several weeks, then left without bombing. At eight o'clock sharp, three planes appeared over Hiroshima. Although the air raid warning was issued at this time, Hiroshima residents did not seem to hear it. People are used to the constant bombing of Japanese territory by American planes. The warning was not lifted until the US military weather plane left. Now, another plane is coming, the alarm is pulled, and the citizens are tired.