Analysis of Weekend Snowstorm February 20-23

After a slight warm up mid-week, a new storm system is approaching Colorado this weekend. The overall pattern that has brought us well above average temperatures and dry weather is beginning to break down and the best evidence is the increase of storms being steered into the state.

Meteorological models are coming into agreement about the possibility of a substantial winter storm this weekend with snow totals ranging between 4 to 18 inches along the Front Range of Colorado. Historically these types of storms tend to skew our weather models towards more snowfall before dropping off drastically at about 18-24 hours prior to the storm, making a very tricky forecast. We will be watching the models very closely Friday night and Saturday morning to see if this occurs.

Probabilistic snowfall models compile numbers from the National Weather Service’s Storm Prediction Center to look at the probability of given amounts of snowfall .This type of forecasting is beneficial because instead of looking at a set range, we can spot uncertainty in different areas of the snowfall forecast. There is quite a bit of uncertainty with this storm system and we can see that based on the wide range given for snowfall totals (4-18 inches) and decreasing totals with each model run. Friday morning showed considerably higher probabilities for larger snowfall but throughout the day the chances have been slowly decreasing. This trend has continued from late Thursday into late Friday, giving us concern that the weather models do not have a solid grasp on this storm system.

Watch the forecast closely going into Friday night and Saturday morning as it may change drastically or verify. At this time for the Castle Rock area the target range for snowfall looks to be in the 6-12 inch range with some locally higher amounts. Plan on dealing with winter weather conditions this weekend with the heaviest snow predicted to occur Saturday evening into Sunday morning and possibly a secondary wave setting up Sunday night as well. In addition to the snow it will be quite cold, with daytime temperatures in the 20’s and nighttime temperatures reaching the low teens to single digits. This winter storm will begin to move out of the state late Sunday into Monday leaving us with clearing but chilly conditions to start next week. With the unsettled pattern beginning to establish across Colorado we are keeping an eye on another storm a bit later in the week.

Article & Research Prepared by: John Braddock – CRCO Weather Center Expert