Would You Survive?
This is a program I found online for seeing what the effects of a nuclear blast would be in a targeted area you select.
Simply choose whether you want to see the thermal, pressure or fallout effects of a nuclear strike, then use the Search to find your target, and then at the bottom of the map, choose the weapon (everything from a 1 kiloton Suitcase or Dirty Bomb, all the way up to an Asteroid Impact), and then just click Nuke it!