My wife, Marilyn, and I visited Yellowstone National Park from May 20-29 of 2012. We had been told to pack clothes for all four seasons and not be surprised if we had all four in the same day. We flew into Bozman, Montana on the 20th and had shirt-sleeve weather as we drove to our lodging, about a mile outside the Northeast entrance to the park. The next day brought the same pleasant weather and I was wishing I'd brought more pairs of shorts and left the thermals at home. But that was the last we saw of that type of weather until the day we left. Most days brought 2 or 3 snow flurries during the day between periods of broken clouds and then a little more snow at night. Never deep snow_just enough to make us appreciate our thermals. Just enough to require using the snow brush on the car and spending 5 minutes defrosting the windshield early in the morning. Never did wear that single pair of shorts that I brought along.
We were fortunate to see and photograph every species of large mammal in the park except for mountain goats. Most of the mammals were shedding their heavy winter coats and as a result sometimes looked pretty shaggy. And, considering the somewhat late snowfall, may have wished their winter coats were still intact.
We took so many photos it will take a couple of weeks to process and post them. Please view all images at original size. Several of the photos are panoramas or larger than 800 px wide so you may need to resize the browser window to see the entire image without scrolling.