I think white bags melt after the beginning of September.
Of course you can! I think a winter white is perfect for.. winter. I'll be sporting a similar color (Coach Parchment) this winter in IL. Adding scarves or fobs can balance out the color. A neutral like white can be changed so easily.
I wear my white bag all year long, actually it's the bag I use most often by FAR. It looks great in every season in my opinion. I think white leather bags are gorgeoussssssss. (That's why I end up having 4 at one time haha.) White RMs have been popping up on both ebay.com and ecrater.com, so I wouldn't pay full price for one. (Then I again I hardly ever pay full price for anything, I'm cheap that way lol.)
Yes, I think cream / RM's Double Cream is definitely a year-round color. I have it and plan to carry it in any season.
Stark white can be a *little* harder to do IMO, but with the right outfit and accessories, I think you can avoid making it look out of season.
I think white is great for all-year use and is considered to be as versatile as black. I would be very careful when you wear it because white and other light colors are high-maintenance and susceptible to stains and color transfer. Also, Wisconsin weather is similar to Chicago weather (read: can get really crappy) so that's another thing to consider.
On the plus side, Double Cream is not supposed to get dirty easily and most wear and tear can be prevented if you regularly clean/treat your bags. HTH!
I actually never understood why you can't wear white bags during the fall season. I think it looks great all year long! Especially for me since I tend to wear darker colors in the fall, I love having a light colored handbag that makes my outfit look sharp and really pops.
Just make sure you protect her from rain, etc. I use the Apple rain and stain repellent spray.