I thought of “frost quakes” for the booms — where the ground freezes and thaws.
As for the horns, all I’ve got is this — we live about five miles from the nearest railroad track. When we have either very humid weather, or when it is “clear as a bell and cold as ****” we can hear train horns.
Wonder if it’s something intermittent and weather-related, like that.
YMMV.
Happens even when it isn’t cold. Go figure!