It is common for us to experience particularly frigid temperatures the night after a snow event. It turns out that there are a number of factors that make cloudless post-winter storm nights anomalously cold: The earth receives energy from the sun during the day as shortwave radiation (ultraviolet, visible, and shortwave infrared radiation), and emits energy at night in the form of longwave radiation (infrared radiation). However, it is important to note that not all of the energy that the ea

When reading a National Weather Service forecast discussion during the winter months, we sometimes come across the term "Conditional Symmetric Instability (CSI)". This was true with our latest storm that is winding down today. But what exactly is CSI, how can we diagnose it, and how does it differ from other phenomena that can dump multiple inches of snow in a localized area? CSI involves heavy, banded snow that has a typical duration of 3 to 4 hours. These snow bands have a length anywher