Using the NCDC climate data from a station in Steamboat Springs (in the valley), we can investigate trends in snow depth and snow fall. With ‘early’ 2016 spring with high February and March daily temperatures, the question about trends in snow depth arises.

The graphs are created by plotting the year on the x-axis and snow depth (inches) on the y-axis for respective months.  The data is colored by day of the month with blue and green colors early in the month, yellow middle of the month, and orange and red late in the month.  Furthermore, 24-hour snowfall (inches) is plotted as a size range.  Large snowfall events show up as large circles.

The March Snow Depth (inches) and Snowfall (inches) graph is shown below.  The data suggests that over the past century, the number of years with  no snow depth (inches) by the end of March has increased.  A linear trend was fitted to the data to highlight the overall general decrease in snow depth through time.  But, there is considerable range in the data.  Early in the century the years with deep snow were approximately 50-55 inches.  In past few decades (1970’s to 2010’s) – the years with deep snow were approximately 35-40 inches.  Also, beginning in the 1970’s more and more years have March ending with little to no snow depth in the Steamboat valley.

March Snow Depth and Snowfall

Let’s look at the other snowy months in Steamboat and see if we can observe other trends.

Starting with November:  Over the past century, the general snow depth trend appears to be increasing.

November Snow Depth (inches)

December:  December snow depth and snowfall values appear to be relatively stable to a slight increase in the past few decades.  Furthermore, by the end of the month, the snow depth is typically ~35 inches.  December snowfall events are ample.

December Snow Depth (inches)

January:  Again, January snow depth and snowfall appear to be stable.  Very few years with no snow at the beginning of the month and almost no years with less than 10-15 inches at the beginning of the month.  By the end of the month, the general snow depth can be expected to be 35 inches.  January snowfall events are not as ample as December (in general).

January Snow Depth (inches) and snowfall (inches)

February:  Snow Depth in February generally ranges between 15 and 50 inches with an average of approximately 30 inches.  February, over the long-term, is a productive snow month.  No significant trend in snow depth.  Snowfall events are more ample than January.

February Snow Depth and Snowfall (inches)

April:  Snow Depth in April over the past century has ranged from 0 to 46 inches.  As expected, the snow depth is, typically, the deepest at the beginning of the month (light blue).  By the end of the month, the snow has melted (red data).  Notice that the snow depth at the beginning of the month has progressively decreased through time (see the graph for March decrease in snow depth).  With a general decreasing trend of March snow depth, it follows that snow depth in April would also trend downwards.

April Snow Depth and Snowfall (inches)