What’s a Normal Winter Anyway? (Boston Edition)

Mid-March is here, and all of Boston is breathing a sigh of relief that this winter was more “normal” than last winter. Last winter was completely record breaking in terms of snow, and we all have a bit of a hangover from it. I was discussing this with a few people at work, and we started to wonder what “normal” really looks like for this area. Obviously this meant I needed a graph!  I wanted to check out what the snow curve normally looks like for each winter, and I found some decent looking data here.  A few notes:

  1. The data is almost 100 years worth….1920 through 2016
  2. After 1936, measurements are from Boston Logan Airport. Apparently that’s when the weather station opened there. I’m not completely sure where they came from prior to that, but presumably it was somewhere in the area.
  3. For all data, the year means “season ending in”. So my 2016 totals include November and December of 2015.
  4. I only looked at November-April.  October and May have both had snow, but the snow that fell in those months has never gone over 1.5 inches for any season.

Okay, so what’s normal?  First I took a look by month. The blue box represents the middle two quartiles, or where half of all years fall. The lines on either end are the top/bottom 25% of years:

Snowbymonth

So it appears January and February are approximately equal for most years, but February can pack a bigger punch.

But let’s just look at averages for the months, then see where last year and this year fall:

Recentyearsvsaverages

Interesting. This shows that this year we actually had a slightly above average February, we just didn’t notice because last year was insane.

Okay, but what about total snowfall? Where are we so far?

Well, since 1920, here’s what it takes to make each quartile:

Min 8 inches
25% of winters < 28 inches
Median < 39 inches
75% of winters < 53 inches
Maximum 112 inches

As it stands right now, Boston has gotten about 25 inches of snow so far this winter. That puts us in the lowest quartile for snowfall. We’re not quite the least snowy winter in recent memory (2012, 2007 and 2002 all had less snow), but we’re certainly on the lower end. Only 18 years (since 1920)

So basically we have a year with legitimately low snow totals that was preceeded by a year with outrageous snow totals.Kind of explains the whiplash.

But where are we on the whiplash scale? Is this the biggest year to year change in snow totals ever?

Well, we hit a record for that this year for sure. An 87 inch difference in snowfall totals for consecutive years is pretty record breaking.  Interestingly though, there were two streaks I found that actually gave people whiplash for 4 years in a row. The  1994-1997 run, where the snow totals swung up to almost 100 inches for two winters (1994 and 1996) and then hit low totals on the alternating years (16 inches and 30 inches in 1995 and 1997, respectively).  2002-2006 was similar, though less dramatic.  In order to compete, 2017 will have to hit 90 inches or more of snow.

Don’t do that 2017, don’t do that.

6 thoughts on “What’s a Normal Winter Anyway? (Boston Edition)

  1. I am surprised that there is about as much snow in March as there is in December. I would have predicted a lot more snow in December than in March.

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    • Yeah, that is pretty surprising. I wonder if that perception is skewed by the lack of snow melting in December….10 inches in March could melt significantly within a day or two, but 10 inches in December could stick around for months.

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  2. By memory, I think we had a significant whiplash in 1969 and 1970. Can you verify if that was one of the tops? I don’t really remember much about 1979 following 1978, but I would guess that would be significant as well.

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    • 1969 and 1970 actually had really close overall totals…52 inches and 53 inches respectively. What is probably throwing you is that 1970 was almost a completely even winter (about 10 inches each month), and 1969 had 40 of those inches in one month with almost nothing in the others. Averages aren’t always very honest.

      The drop in 1979 was 56 inches….making it 11th overall.

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      • Feb 69 must still stand as one of the top months, and now that you bring up these stats, I do remember the ground being bare when it started snowing around my birthday.

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