A fun weather day! The cold air really never drained away from the higher terrain of the Pikes Peak region. In fact, it was being pushed up against the southern slope of the Palmer Divide all day long and we spent most of the afternoon in the teens with clouds re-developing and even some flurries and light snow showers. The edges of these shallow airmasses after the main system moves through is a situation our computer models frequently struggle with and many times we just have to observe what is happening now, project it mentally 6 hours out, and then re-evaluate. The key to tonights forecast is leaving clouds and areas of fog in as possibilities until we actually see the wind switch around out of the north or northwest. That will indicate drier air pushing off of the mountains and will signal the onset of the airmass draining away. Much like water in a bowl, these cold/shallow airmasses seek the lowest lying areas because they are very dense (”heavy” due to gravity’s influence on it) and will end up exiting eastern Colorado along the Arkansas River.

Until this process happens, we’ll see areas of low clouds and fog for areas that are high enough, such as Monument and Briargate as of mid-evening.