Air Force weather forecasters said there is a 70 percent chance of acceptable conditions Monday afternoon for the 4:58 p.m. EDT launch of the SpaceX-3 mission. The concern is that thick clouds will develop during the afternoon as the countdown winds toward liftoff. If the launch is scrubbed Monday, the next opportunity will come Friday, April 18. Conditions that day are expected to be worse than Monday’s, with the forecast calling for a 40 percent chance of acceptable weather.