How to weatherproof a screened-in porch

We have a screened-in porch on the north side of our house. The screen panels are too large to install removable glass (probably too expensive) but the rain in the winter blows all on the porch. I know some of these restaurants that have outside eating porches have some type of roll-up plastic curtains they use to make their porches weatherproof and I thought that might be an option for us. I have looked on the net but cannot find what I am looking for. However, I might not have used the right wording. Does anyone know where I might can see about these curtains or perhaps have a better solution. I will eagerly await a reply and will thank you in advance.