Had not fully thought that one through.
Would disconnecting your house via the main breaker prevent that?
Assuming the breaker pops with the surge. Assuming there isn't an arc over the open breaker. Assuming you don't have a fire start in your walls before the breaker can pop.
If you know the event is underway, you can pull your own breaker and be vigilant with respect to the buildings adjacent to your own home. You might still have arcs occurring in the breaker box that would imperil your building.
On the “main breaker,” the power line going to the house from the power company’s poles or ground junctions are always connected to the box. Depending on the amount of power in a pulse, arcing may or may not cause a fire. Unlike with some appliances (solid state and micro stuff) it would take a monstrous pulse to cause fires through residential electrical systems. Highly unlikely and rare. Old shacks of the 1800s were much easier fuel for fires than contemporary houses. See fireproof sheetrock and wherever it might be needed, though (any bare wood above a switch?).
It’s always a good idea to have fire extinguishers around though. Ten-pounders are good. And here’s an idea. Some race cars have had little auto-extinguisher systems on them. Might be able to build an automatic system for a house with something that would provide more volume (more foam, halon or whatever).