Borderline freezing temps - options?

We will be in a cold area at the end of next month. Averages for the month of March at the campground are a high of 54 and a low of 33F. Since we are at the end of the month we might be just fine. I am trying to figure out ahead of time how to react if gets colder than normal and the temp decides to dip from 50s in the day down to 30 or so at night. 

I would rather not winterize if at all possible but I will be prepared to do so if a more severe cold front comes through. Mostly I want to figure out how best to handle a borderline temp that is slightly below freezing at night. What do you think? Would it be ok through the night if it hits 30 or so? Is there a way to make it less likely to freeze? Dripping water in the sink, electric blanket on the exposed pipes? Open to any ideas here.