[Gritty]

A Carrington event style of flare that runs 2 days would surely set most homes and businesses on fire

Wouldn't our main breaker box prevent that by tripping the breaker or would the surge be so fast and overwhelming an immediate fire breaks out?

[DuncanWaring]

The “Carrington Event” appears to be caused by a large solar flare, so we would have at least a few hours notice.

I suspect disconnecting your main breaker would isolate your house and prevent fire damage to it, even though you would be without electricity for quite some time after the flare had passed.