April is winding down. I was sitting on post this until the end of the month. After all, we've had light snow in late April even early May in recent years so I wanted to be sure we could put a bow winter and store it away.
How do we accurately measure winter as a whole? More specifically how do we define a harsh winter? No one gold measurement standard exists.
Over the years, I've been toying with different ways to appropriately answer this question. I've posted this question on social media several times. What I found out was that everyone remembers winter in their own way, much of which is strongly influenced by personal events that occurred coincident with specific winter weather events. All of which seems highly subjective and personal.
We all see the weather through our own personal preset lens. Highly personal memories can alter our baseline perspective on weather (strong recency effect) especially when comparing current weather to past weather. I remember posting follow up questions in response to many comments about winter. Some took the responses personally. Their experiences were strong. These helped reinforce an already established weather vantage point. Their perspective was steadfast. Good luck changing it. I quickly found that the entire project slowly became an exercise in recognizing cognitive bias and recency effect.
Knowing all of this, I compiled several standard metrics (average temperatures and snowfall) used by the National Weather Service and NOAA with a few that I like to call "non-traditional metrics" that attempt to take into account public perception, recency effect and overall bias as outlines above.
The result was a 21 different metrics that measure different components of the winter as a whole. There is no 100% completely objective way to determine the harshness of winter but I think this is a great move forward.
Here is the list in no particular order:
- Snowfall vs normal
- Average temperatures vs normal
- Days with snow on the ground between December and February
- Days with 1" snowfalls November through April
- Days with 4" snowfalls November through April
- Days below normal - DJF
- Days below normal - January/February
- Longest stretch highs under 30
- Days with Highs under 30
- Days with highs above 40
- Days with highs under 20
- Nights below zero
- Days Wind Chill below zero
- Days Wind Chill below -15
- Longest stretch below normal temps DJF
- Longest stretch snow on ground 1"+
- Days under 30 degrees & wind gusts 20+ mph
- Longest stretch between 40 degree days
- March snowfall
- April snowfall
- Days between first and last snowfall
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I calculated all 21 metrics for each winter going back to the late 1940s. Some of the wind chill data had to be reconstructed using temperatures and wind speed prior to the early 1970s. Once the numbers were found, I calculated a 15 year average for each one working back in time starting with this winter. So the first 15 year period was 2011-2025, the second was 1996 to 2010 and so on. My goal was to compare winters to the average of the winters close to it. Each winter metric that was "harsher" than the 15 year average, I colored the block blue.
First chart is colored blue with the actual numbers. The second is without the actual numbers and looks cleaner.
You'll notice that most of the extreme winters we remember are represented. While this past winter (2024-25) was by most measures more "winter-like" than recent years, historically it was in the middle of the pack with 10 of the 21 metrics checked.
Here is the entire chart for reference: DOWNLOAD it since its a large image.
Chart without numbers. DOWNLOAD it since its a large image.
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