Fortunately it is only going down to 4 degrees tonight, but a floating row cover can help!
If you don’t have one, an old sheet will do the trick. The sheet would need to come off in the morning to let the sun in. The floating row cover can stay on for the next week or so to give you a 3 or 4 degrees extra warmth, protect from weed seeds blowing in on the wind and hungry animals that are looking for tender greens after a long winter.