The next mass shooting will take place on February 12, 2014, in Spokane, Washington. It will be committed by an emotionally disturbed, 38 year-old white man who will kill seven people and wound six more at a place he used to work using a semi-automatic handgun he purchased legally in the state.
It's important to note the US has sunk so far deeply into gun violence--with the invaluable assistance of a terrorist organization, the NRA--that we are able to make such predictions. Just like we can predict the frequency of hurricanes. More:
Our sincere hope is that every prediction we made is wrong because no mass killings should happen again. The probability of that happening is not statistically significant.