Rally Points, near, far and distant.
For us, it's across the street (near), at the coffee shop (far), because its out of line of sight and easy to get to. The distant Rally Point is in another city that likely won't be affected by the same event.
Points of contacts you can notify if you are separated., near, far and distant, as in another state. Don't discount the mail especially to contact the distant POC. Everything else may be screwed but the Postal Service is pretty reliable. A postcard to your far POC could be useful.
The book of face has an emergency location option that they turn on in a declared emergency or sometimes for big events.