Winter Weather in Colorado Springs:
a Summary for PPARES

Monday, October 31, 2005

Al Glock, KC0PRM (@arrl.net)

As a “warm-up” for writing articles for the PPARES web site, I did a little research into the kind of weather we can expect over the next several months.  Winter’s not officially here, of course, but we’ve already had enough snow (October 10) for our El Paso County Search and Rescue friends to have had a busy day.  What I’ll do below is give an idea of what we might expect based on the history of winter storms in the Colorado Springs area.

Daily snowfall averages over the last 30 years are presented in the chart below.  The average snowfall for each day is calculated by totaling all the snow that ever fell on 1 November over a 30 year period and dividing by 30.  The result is 0.1 inches of snow.  While this isn’t representative of the amount of snow that could fall, it does paint a picture of the likelihood of snowfall.

The interesting aspect of this chart is that there are two peak periods of snow likelihood—one in late November to early December, and another centered around mid-March.  As you can see, the springtime has historically produced more snow.
Another way to look at winter storms is to examine the history of blizzards.  When are they most likely to occur?  An analysis of recorded weather in Colorado Springs for the last 100 years reveals the following blizzard history:

At the beginning of November, we’re heading into a time where there’s been a fair amount of activity.  So while we’re planning for turkey, holiday guests, and time off from school and work, we also should be planning to keep the gas tank full, and the go-kits ready.
Notice, too, that most of the blizzards occur outside of winter.  Of the 21 recorded blizzards in the chart above, only nine happened between December 21 and March 20. 
Another interesting chart considers the number of days that have had at least one inch of snow on the ground.  For example, the longest recorded period where there was at least 1” of snow on the ground in Colorado Springs was from Nov 27 to Dec 30, 1972.  The collected data over 50 years results in the following chart:

You can see that December is the most likely month where we’ll have to go with several days of snow on the ground, and February comes in second.  Snow on the ground equates to bad driving conditions and the increased likelihood of needing chains to keep from getting stuck.
Other links:

• The Colorado Springs Office of Emergency Management has a checklist of winter preparedness items for your home and vehicle.  This list is at http://www.springsgov.com/Page.asp?NavID=5304.
• The National Weather Service in Pueblo has their winter preparedness page at http://www.crh.noaa.gov/pub/wcm/Winter_Week/winter_week.php
• And finally, do you remember the “Skywarn Spotter” song that Tom Magnusson played at the Skywarn training last April?  The composer of that piece and numerous humorous others has a winter storm song.  It’s at http://www.srh.noaa.gov/elp/wcm/Winter%20Storm.mp3.  The music is written and performed by John Fausett, the Warning Coordination Meteorologist (WCM) at NWS El Paso, Texas.