I Dropped A 1,000 Kiloton Device On Hanscom

And you will never believe what happened!

The inner yellow circle is the fireball, the next area is the widespread blast damage ring, then thermal damage (3rd degree burns if you are in the line of sight, which could be very possible given that this is a 10,000 ft air burst)  finally, low blast damage--think windows broken.

I'm not saying we wouldn't get our hair mussed, but this is only about 10 miles away, 50 times as powerful as what was dropped on Nagasaki and we would almost certainly live through it.  The deaths are predicted to be over 50 thousand, which sounds low to me.  The site for this is here if you want to check it out.