This is bad. UPDATE 02-17-21

[Tommymac]

8. Make sure you leave a faucet or two open.

Frozen pipes are bad but you can also alleviate some pain by putting an old fashioned 100 watt light very near the pipe where it comes into the house. As long as you have power this will help thaw them.

Another trick is to sink a piece of iron rebar into the ground so it makes contact with the buried pipes in your yard, then attaching a car battery to it via jumper cables. The current will transfer to the copper or iron pipes and help thaw them underground.

Of coarse if the underground pipes are plastic then this is not going to work that well.

Good luck.