Snow cover and high temperatures

 

Even though the heavy snow is over with, we will still feel the effects of snow cover on our high temperatures today. On a typical sunny day, with no snow on the ground, light and heat from the sun can easily make it all the way to the ground, allowing the heat to build at the surface, and increasing our temperatures during the day. But, with snow cover, most the sun's light and heat is reflected and bounces back through the atmosphere, which helps keep our temperatures on the frigid side. Why is that?

Dry ground can easily absorb the sun light and heat, allowing temps to warm.

Snow, however, reflects most of the sun's light and heat, which keeps us colder.

Well, the ability for a surface or object to reflect is called its albedo. It's just a number on a scale from 0 to 1. Snow has an an albedo of 0.9 while normal, dry ground has an albedo on 0.25. This means that snow does a good job at reflecting but a poor job at absorbing. The exact opposite is true for dry ground. 

You can easily see the drastic difference in temperatures across the state of Indiana. South Bend, and the rest of Northern Indiana, should only see highs in the mid to upper 20s. Meanwhile, farther south, Indianapolis will hit a high of 34. Not only because they are farther south, but they have 0" of snow on the ground this morning, allowing them to warm above freezing. 

Indianapolis has no snow on the ground, which means they'll warm into the 30s. That's not the case for snow-covered Northern Indiana.

Don't worry fair weather fans, our warm-up is on the way. We'll just have to wait until Wednesday and Thursday.