Quote Originally Posted by DavidEduardo View Post

The ITU now says that 15 mV/m is the minimum needed AM signal to cover an urbanized area. Under that standard, the coverage of WABC is not that significantly greater than that of an ESB FM signal.

Night skywave is irrelevant. Very little radio listening happens then, and nearly no buying takes place. And nearly no listening to out of market AM stations at night can be seen anywhere in the USA.
I am probably one of the few that listens to AM stations out of my area at night [WCBS, CFZM, etc.] Even ordered something from a WCBS advertiser once so buying does take place. Granted, probably no one under 50 listens to out of market AM stations at night but if they follow a certain sports team that is broadcast on that AM station and that doesn't have an affiliate in where they live, they might try and tune it in [if they even remember that AM still exists.]