Click here for one portrayal of the results after a surface blast of the current Chinese "Dong Feng" 5 megaton (million tons TNT equivalent) ICBM fusion weapon (largest on the planet), centered on Washington, D.C., 15 mph wind toward Buffalo, NY, USA.
Immediate casualties only are given; they seem underestimated. Note: there are ~6 million persons living in the Washington Metropolitan Area.
Longer term radiation (including fallout) morbidity and mortality are not presented.
The 35 cal/sq. cm. thermal radiation radius is the area - in this case a circle 16 miles in diameter - wherein all wooden buildings would spontaneously ignite.
The 1 rad/hour fallout radiation contour reaches beyond Toronto, Ontario, Canada.
This radiation exposure rate is ~100,000 times the background external radiation rate (~10 microR/hour).