How did that meteor know to hit that hole?
150 megaton weapon, 2000 meter air burst, just to make sure you get them all.
Overpressure should flatten everything within about a 32.6 kilometer radius, and heat pulse should fry everything in about a 6.1 kilometer radius of ground zero.
Estimated casualties (KIA) from blast would be about 1.2 million, casualties from overpressure damage would be about another 1.3 million fatalities.
Yes; I have thought about this a lot.