Insider Blog: Why these snow piles aren’t going anywhere anytime soon

Over the next few days, as temperatures climb and roads and parking lots get plowed, you'll start to see less snowy roads and more of those large piles of plowed snow sitting around.

There are many factors that affect snow melt but for this explainer, we're going to focus on three key variables.

First is air temperature. Obviously, when air temperatures are above freezing, snow melts.

Second is Sunshine. Sunshine is a big factor in snow melt. In fact, even when air temperatures are below freezing, incoming solar radiation is absorbed by the top layer of snow cover, causing some to melt.

Last, but maybe the most important is density, or basically how wet or dry the snow is.

When snow is shoveled or plowed into a large pile, snow that was spread out in a relatively thin layer across the ground, gets squished together into a large cold mass of moisture.

At first, just the shear size of the pile will insulate it's inner layers of snow.

After sunshine and air warm temperatures begin to melt the outer layers of snow, that snow melt can seep into the snow pile. This makes the pile of snow more dense, harboring more moisture in less space. A pile of more dense snow can both be slower to warm and cool than a fresh blanket of snow on the ground beside it that is more exposed to warmer air.

As temperatures gradually warm and reveal the ground, the increased density of snow piles may keep them standing in the presence of warmer air on sunny days.

There are many variables that determine snow melt including wind, precipitation, and more; but simply put, a higher density object takes more energy to warm or cool. That can help us understand why today's snow mounds will likely be with us for a few more weeks.