A draft explosion is a term coined by Blake McPherson (@Notorious_BRM). He saves all his ridiculous and generally bad tweets in his draft box then tweets all of them at one time. This sending of usually 15+ tweets at one time is called a "draft explosion."
"Man did you see Blake's draft explosion last night?"
"Yeah dude it was totally rad, I died laughing at one tweet and all the others made me want to hit my phone with a sledgehammer!"