Why mild-winter areas get hit harder
Homes in places that freeze every year are built for it — insulated crawlspaces, pipes run away from exterior walls, heat tape as standard practice. A lot of Pierce County housing stock wasn't built with that in mind, because it usually doesn't need to be. The problem is 'usually.' When a real cold snap comes through, exposed pipes in an uninsulated crawlspace or an exterior-wall bathroom are the first to go.
The pipes actually at risk in your house
Anything running through an unheated crawlspace, an exterior wall, a garage, or an attic. Kitchen and bathroom pipes on outside walls are common trouble spots in older Bonney Lake and Sumner homes especially. If you've ever noticed a specific faucet runs noticeably colder or slower than others, that line is probably more exposed than the rest of your plumbing.
What actually works before a freeze warning
Disconnect and drain outdoor hoses now, not the night of the freeze. Know where your main shutoff is and make sure it actually turns — a valve that's seized from years of not being touched is useless in an emergency. On the coldest nights, let vulnerable faucets drip slightly (moving water is much harder to freeze) and open cabinet doors under sinks on exterior walls so warm household air can reach the pipes.
If a pipe already froze — or burst
A frozen-but-not-burst pipe usually shows up as a faucet with no flow. Shut off the main if you suspect a burst, not just the frozen fixture — a frozen pipe that thaws while you're not watching can flood a house fast. If you're not sure whether it's frozen or already split, treat it like it split and call. Better to have someone confirm it's fine than to guess wrong on this one.