It's been a long time since I've calculated nuclear blast effects and downwind fallout hazard, so this is pretty rough.
Bomb Type: B83 1.2 megaton fusion warhead
Equivalent Yield: 1,200,000 tons of TNT
Prevailing Wind: West to East
Estimated Impact of 1.2 megaton ground burst over downtown Boulder:
Inner Red Circle—Area consumed by firestorm
Outer Red Circle—Probable total area of the firestorm
Red Arrows—Downwind Radioactive Fallout zone
The Federation of American Scientists provide an excellent description of the effects of a nuclear blast at this link:
http://www.fas.org/nuke/intro/nuke/effects.htm
The Nuclear Darkness website has a tool that allows you to simulate the blast effects of a
nuclear bomb on a specific location. Pick a target location, pick a blast yield (1,200 kt for a B83) and see how it plots out on Google Maps.
http://www.nucleardarkness.org/nucle...sionsimulator/