Sometimes, just a small hint is enough to give players image of what's going on and give them the right feel. And perhaps help everyone remember some environmental modifiers too. This is true with the torch & light markers I made years ago, in addition to helping to remember that characters can't see everything out there.
This time I created just a few pieces of trees and some other minor components that can be added to a scene to remind what season it is – which I believe is often forgotten. These pieces have Autumn trees on the other side and pieces fitting for early spring or warmish winter on the other side. I've photoshopped them from materials that can be found online. Remember, google something with site:dundjinni.com or use image search with search words of your choise and choose 'transparent' as color.
Note that the edges of the pieces don't look that sharp when looking at them live, the photo seems to emphasize them.
Summer doesn't need anything and full winter need maps of it's own, if you want such. Summer can be emphasized by use of lightning & sound, which I talked in another post, and plan to focus more in succession post for that one.