Proceeding with the burn risked disaster if control was lost, as indeed happened. However, not doing the burn might also have been disastrous because the entire southern slope of Cerro Grande was tinder-dry and ready to ignite catastrophically in the event of a lightning strike (hardly unusual in the Jemez in the spring) or human carelessness with fire. The same winds that militated against starting the controlled burn might then have driven the uncontrolled fire toward Los Alamos, with terrible consequences. In any case, the controlled burn was indeed initiated on May 4, and things rapidly got out of hand.