Okay - this is just done digitally, but maybe you could do something like this:
Mount the shutters with some kind of shutter hinge so they would close over the opening and put temp plexiglass inside the house. You might even be able to do like CityChook mentioned. Mount a piece of plexiglass in a frame that would fit into the window, then take it out when it's warm. The right hardware would still let the shutters open and close.
This kit is adorable - I was actually looking for it when I came across the one I ended up with.

Mount the shutters with some kind of shutter hinge so they would close over the opening and put temp plexiglass inside the house. You might even be able to do like CityChook mentioned. Mount a piece of plexiglass in a frame that would fit into the window, then take it out when it's warm. The right hardware would still let the shutters open and close.
This kit is adorable - I was actually looking for it when I came across the one I ended up with.