There are a number of reasons for why the ABS system will fault and show the warning light meaning it's turned itself off. I've not had that problem in our new V40 after 8800mi but when I had a Saturn it would happen one or two days every summer, usually on the hottest day (99F or hotter; also there was very high humidity (NC))and it would reset itself after I'd let the car sit. Once I called Saturn customer support and they recommended checking the fuse and pulling it out and resetting it and that fixed it instantly (fuse wasn't blown).

Usually it happened after I gave the system a nice workout while I enjoyed a spirited drive. In that instance it was certainly either there was some condensation in the brake lines that vaporized giving the system a fault, or the sensors or some other part over heated.

I drive an Integra and it's only faulted once since new (73000mi on the odometer now). My best friend also had an Integra and his faulted in the summer once a year, probably same conditions as in my Saturn (except he didn't drive as agressively as I did).

In your case it could be some snow or ice got thrown up into the gears/sensors that check wheel spin. Unless a code was recorded there shouldn't be much to worry about. I know you'll probably not like my response but this has been my experience with ABS. I think I did have a code recorded once in my Saturn (when I had them check once) but it was nothing to worry about... I think it was from having pulled the fuse... I'm not sure now.

Alberto