|Albion Basin and Greeley Hill, 8 June 2014|
On May 11th, the snow depth at Alta-Collins sat very near its maximum for the year at just under 120 inches. At that time, the snowpack was fairly consolidated and ripened, meaning it has warmed to 0ºC throughout its depth, so additional energy input from above freezing temperatures and solar radiation would result in snowmelt.
Indeed, it was just a couple of days later that temperatures popped up to near or above average and, despite some ups and downs, they have stayed there for nearly a full month.
This has led to a non-stop decline in snow depth at Alta–Collins. If you look carefully at the graphs above, you can also see that the rate of snow depth decline increased around May 25th, which is also when there was somewhat of a step up in the temperatures (especially the maximum temperatures). Since that day, we've been losing about 2.8 inches of snow a day.
On May 19th, I guestimated Alta-Collins would lose all its snow around June 27th. That's still looking like a decent guess, although the current melt rate would bring an end to snow cover at that location at around June 25th.