Let it stop, let it stop, let it stop

Here in Washington, DC we certainly have not see the anywhere near the snow totals that Boston has seen this winter. But I am certainly tired of shoveling! Has the Snow Finally Stopped? is a question that Harry Enten at Five Thirty Eight's Data Lab has examined using data on the date of the last measurable snow over the last 50 years in various US cities with data from the National Oceanic and Atmospheric Administration (NOAA).. In the graphic above he plots the lower and upper quartiles of the date of the last snow along with the median. For Washington, DC here is a stemplot of the frequency distribution of those dates.

December  0 | 9   
          1 |   
          1 |   
          2 |   
          2 |   
          3 |   
January   0 |   
          0 |   
          1 |   
          1 | 5   
          2 |   
          2 | 57   
          3 | 1   
February  0 |   
          0 | 7   
          1 | 12234   
          1 | 5789   
          2 | 0334   
          2 | 577   
March     0 | 12   
          0 | 567888899   
          1 | 023344   
          1 | 8   
          2 | 011   
          2 | 5567   
          3 |   
          0 |   
          0 | 777

It's interesting that the overall latest measurable snow in Washington, DC has only occurred on April 7 (in the three years: 1972, 1990, and 2007). Reminds me of another early April pattern that held up for years. 

Over 3/4 of these snow dates are behind us now. But, there are still 11  years out of the past 50 that saw measurable snowfall after today's date of March 16. Based on these data, we can estimate the chance of more snow to be 22%. Let's bet against it!