Click to enlarge. La Nina is clearly visible here: anything south of about Tierra Amarilla, NM has really missed out (though it looks like the Whites in Arizona got a little love yesterday). The snowpack in the Great Basin and Utah is seriously insane, 300% of normal in a lot of areas, and normal is already a lot of snow in the Wasatch. It's going to be quite a year on the Idaho rivers, and a crazy awesome year on the Yampa.
Yeah, there are definitely some statistical anomalies represented, like the Cimarron headwaters and eastern Arizona sections. A couple inches of snow in those areas where average is basically nothing in late May produces some misleading percentage numbers. I assume that effect also accounts for the lowly 20% number in the Gila, which definitely has zero snowpack worth noting right now.