Heading for the woods in a survival situation is so far down my list that it isn't even ON my list. That scenario is movieland only.
I can really only envision two situations right at this moment that involves leaving home: wildfire or toxic spill, and both of those are likely short-term. Flood is a possibility here, but more in the marooned sense than the underwater sense.
House fire or earthquake, I'll camp in the yard.
Power outage (local or widespread) or volcano eruption/heavy ashfall, I'll camp out in the house.
My biggest possible bugaboo is being away from home during some Big Deal and having to get home to my supply of stuff on foot with minimal supplies.
As Blast pointed out, if you've got kids (or seniors or disabled people) with you, heading for the woods is a REALLY BAD DECISION.
Sue