Here in the Denver area we've experienced an unusually long period of snow cover on the ground (60 days and counting!). The moisture is most welcome, but some lawn areas may be susceptible to snow mold. On my lunch-time walk today, I spotted this patch on a neighbor's lawn. As you can see, this grey form looks like a spider web stretched across the grass. The best treatment at this time is to simply rake the affected lawn area to help it de-mat and dry out. If necessary, the area can be over seeded later in the spring when the soil temperatures warm up(about Memorial Day here). For more information on additional treatment, check out this article from the hort experts at Cornell.
