Help! No power!

I am in Texas and we have lost power. Our house is getting down to the 40s and 50s. Power had been out for 2 days. Tips on how to keep my 3week old baby warm? This is uncharted territory for us and the power could be out for a few more days. We don’t have lots of warm clothes for this. I know we can’t put blankets in his crib but in just a swaddle he seems cold. I have kept him bundled the last 2 nights but it’s going to get colder. We are also at risk of losing water. Any advice? Anything you know of that I can do to prepare? I know some of you in colder places probably have ideas.