Skiing here in late March can be a gamble. Two years back as mentioned the snow was soft and slushy by then. Last year, if you can believe it, we closed early but had some of the best conditions of the winter as soon as they announced the early closing! We couldn't believe they actually closed the place with all that snow.
Hellroaring Basin closes 4/1 which is major in terms of acreage, minor in terms of "on piste" stuff.
The "back side" holds its snow wonderfully even into March because of its northfacing slopes and the sun not reaching down into that section for much of the day. The trails there are pretty easy, except for Big Horn, Marmot, and Black Bear. There is some tree skiing also for those who like back country stuff.
The front side will be soft as you descend, like anywhere else at that time of year. You'll need to understand the faces and think about what is going to soften first and plan your day accordingly.
Yesterday was probably one of the most beautiful days ever here. Perfect snow, lots of it, navy blue sky, visibility into Canada and Idaho, no crowds. Today however was rainy or "falling slush" at best. We tend to like the fog here as the snow lasts longer that way -- people were griping about the sun as they knew that more than one day of it would change the powder to, well, just "snow".
We had loads of beautiful "inversion days" from opening until mid-December, then mostly fog or snowy days from then until yesterday. Looks like we are back into "low flying clouds" again.
Recent pics can be seen here