Walk into any home improvement store this time of year and you will be hard pressed not to find the obnoxious, in your face, advertisements citing unsubstantiated facts about the upcoming winter–“colder and snowier than normal winter predicted (most likely by the sales manager), are you prepared?”  With the rare October snow event forecast for our area this weekend, you are now going to see even more outrageous assumptions and claims.  Every sales manager is going to jump on this notable early season snowfall as a premonition of things to come for this winter season. However, let’s remember the main purpose of these big box home improvement stores.  They want to sell you things and not act as your trusted local climatologist.  Unfortunately, consumers all too often fall victim to these advertisement gimmicks that are rooted in psychology.  They get convinced that it is necessary to have that 8.5 horsepower 36 inch wide two stage snow blower with electric start because they remembered a time when an early season snowfall resulted in a doozey of a winter.      

When we believe that there is a relationship between two things, we are more likely to notice and recall instances that confirm our beliefs.  In psychology, we call this the Illusory Correlation—a perceived but non-existent correlation.  The Illusory Correlation can explain why people say that it always rains after washing the car, that infertile couples are more likely to conceive after adoption, and that changes in weather trigger arthritis pain.  I could cite many more examples of this psychological phenomenon but the point is that our tendency to acknowledge random coincidences as correlated events can easily trick us into seeing what is truly not there.  We may legitimately remember a year when an early snowfall led to a much colder and snowier winter season overall.  However, we tend to forget all the times that it did not. 

Although the local home improvement store managers would like you to believe that their advertising slogans are reliable predictors of upcoming seasonal patterns, we know that much more is involved in the science of meteorology and climatology.  Yes, meteorologists still have the stigma of being error prone (unfortunately for them they all cannot be the local meteorologist for San Diego, CA where is it 75 degrees and sunny a majority of the days throughout the year).  However, technology has vastly improved the accuracy of day to day and seasonal forecasts. No longer do we have to rely on the old Farmer’s Almanac or local home improvement store to know what could possibly be in store for an upcoming winter season.  There is a whole field of both private and public entities that are dedicated entirely to studying various global climate patterns to help make these broad general predictions months in advance.

One of the areas that gets attention in these much publicized winter forecasts are the Northeastern and Mid-Atlantic regions of the United States.  The high population density and variability of winter patterns from season to season create the perfect recipe for the media to over-hype and sensationalize these forecasts when they are predicted to deviate from what is considered normal. 

As of late, our winters have been anything but normal. The last three seasons have produced above average snowfall with the winter of 2009-2010 taking the grand prize with 78.7 inches of the white stuff falling  in Philadelphia—an all-time record. There have been only three other times since 1884 that Philadelphia has experienced more than 50 inches of snowfall in a winter season—1898-1899 with 55.4 inches, 1977-1978 with 54.9 inches, and 1995-1996 with 65.5 inches—and only four other times where the City of Brotherly Love has seen four or more consecutive years where snowfall exceeded 20 inches (the average is around 21 inches).   Will this year mark the fifth time?  Only time will tell.

The most widely known influence on our weather is the phenomenon of El Nino/La Nina. This winter will mark the second year in row that we will be in a La Nina state.  This is significant. However, because our atmosphere is complex, there are many other items to consider in making a winter prediction.  One must look at the significant implications of other global climate patterns like early season Northern Hemisphere snow cover (especially over Siberia and Northern Canada), the PDO (Pacific Decadal Oscillation), the NAO (North Atlantic Oscillation), and SST’s (Sea Surface Temperatures) along the Atlantic Seaboard. All of these factors are combining this year to paint a picture that should be pleasing to the snow lovers among us—particularly those of us looking for a few snow days.

This upcoming winter season is shaping up to be slightly above average in terms of snowfall with temperatures probably falling just slightly below the thirty year norms.  I do believe that Philadelphia will see between 25 and 30 inches of snow with some significant cold blasts reminiscent of the winters of the late 1970’s.  Between these cold blasts there will be some mild spells teasing us with hints of an early spring.  This winter will be marked more by the quickly changing patterns and not ones that stay in place for weeks or months at a time.  

Winter in this neck of the woods really is a rebel season.  My first winter prediction is just an attempt to make an educated guess at what Mother Nature has in store for us.  Unfortunately, no matter how much technology and knowledge we have gained regarding seasonal forecasting sometimes Mother Nature just wants to do her own thing. 

Until next time, think positive…think weather.

The Competition

In addition to my first winter prediction, over the last several years, I have had a friendly competition going on with Mr. Manero regarding the number of snow days, delayed openings, and early dismissals from school  we will have in a given winter season here at North Penn High School.  You will find our predictions below.  Make sure to follow along this winter and see how well we do. 

Manero’s Predictions:

Snow Days                   3

Delayed Openings      2

Early Dismissals             1

Veneziale’s Predictions

Snow Days                   3

Delayed Openings      3         

Early Dismissals             1

Quick Weather Fact

The last time Philadelphia saw more than 2.0 inches of snow from one single snow event prior to Halloween was on October 10, 1979.